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英语作文关于未来大学生活的作文

英语作文关于未来大学生活的作文全文共6篇示例，供读者参考篇1My Future College LifeHi there! My name is Timmy and I'm in 5th grade. I've been thinking a lot about what my life will be like when I'm older and go to college. It seems so far away, but my teachers say it will be here before I know it! I imagine it's going to be a really exciting adventure.First off, I'll get to move away from home and live on my own in a dorm room. That means no more little brother bugging me or parents telling me when to go to bed! I'll have a roommate though, which could be fun if we get along well. We can stay up late playing video games and eating pizza. But we'll have to be careful not to make too much of a mess or the RA (that's the Resident Assistant who is kind of in charge of the dorm) might get mad at us.The classes in college sound really interesting from what I've heard. We'll get to pick our own schedule and courses instead of just having the same ones every day like in elementary school. Ithink I'd like to study things like astronomy to learn about planets and galaxies, or marine biology to learn about cool sea creatures. Maybe I could even get a scuba diving certification! How awesome would that be?There are supposed to be lots of clubs and activities to get involved in too. I'd definitely want to join an intramural sports team, probably soccer since that's my favorite. Although I've always wanted to try rock climbing, so maybe I'd do that instead. Or both! They say you can try all kinds of new things in college that you couldn't do before.Speaking of professors, I bet they'll be really different from the teachers I've had so far. From what I've seen in movies, some of them can be pretty quirky and eccentric. Maybe I'll get one who is a genius but also kind of absent-minded and forgetful. Or maybe one that seems mean at first but is actually nice once you get to know them. Hopefully none of them will be boring though and will make their classes fun and interesting!One thing I'm really looking forward to is joining a fraternity. That's kind of like a club but where you get to live in a big house with all your friends. We'll be able to have awesome parties and make crazy pranking the other fraternities! Of course, we'll still have to follow all the rules and not get into too much trouble.But it's going to be so cool getting to be part of that brotherhood.There's just so much to look forward to about college life beyond just classes. I'll finally get to experience living independently, making new friends from all over, joining clubs and sports, and maybe even going on a Spring Break trip somewhere tropical and sunny! It will be a total blast.That said, I know it won't be all fun and games. It's going to be a big transition from living at home and will take a lot of hard work and responsibility on my part. I'll have to learn how to manage my time, stay focused on my studies, wake up for early classes, figure out how to do laundry and feed myself, and not blow all my money on junk food and video games right away. It's going to be a huge growing up experience for sure.But I'm ready for the challenge! These are supposed to be some of the best years of your life where you get to discover who you really are before heading out into the "real world" as a grown-up. I can't wait to spread my wings, try new things, make life-long friends, and just soak up all that the college experience has to offer. It's going to be amazing!Those are just some of my thoughts about how I envision my future college life. Maybe it will be totally different than I'mpicturing, but I'm really excited to find out! I've got a few more years of elementary and middle school to go first though. For now, I'll focus on studying hard, having fun with my friends, and getting ready for that next big adventure. College, here I come!篇2My Dream of Going to UniversityHi there! My name is Timmy and I'm 10 years old. I'm in the 5th grade and I absolutely love school. My favorite subjects are math, science, and reading. I especially love learning about new ideas and discoveries. That's why I'm really excited to go to university one day!University is where you go after high school to get an even better education. From what I've heard, it's like the ultimate school. You get to pick your own classes on virtually any topic you can imagine. Want to study dinosaurs? They've got classes on paleontology. Into computers? You can major in computer science or programming. There are so many amazing options!I think university must be amazing because the students are all grown ups. That means they get to make their own decisions about what to learn and what classes to take. No more being told what to do by teachers and parents all the time! Of course, theystill have to listen to their professors during lectures. But university students are considered adults who can manage their own lives.Another thing I'm really looking forward to is living on my own in a dorm room or apartment. No more having my parents nag me about cleaning my room or doing chores. I'll get to be totally independent! That will be so freeing. Although I probably shouldn't go too crazy with that new freedom...I'll still have to be responsible and get all my work done. But having that independence will be awesome.From what I understand, university is also a great place to make new friends. You'll be surrounded by thousands of other students, all roughly the same age and with similar interests. I'm sure I'll be able to find people who love video games, sports, or whatever hobbies I'm into just as much as me. We can hang out, study together, debate intellectual topics, and have lots of fun!But I think I'll be up for the challenge. I'm a very dedicated student who loves learning new things. Thanks to all my great teachers over the years, I've built up fantastic study habits. I always get my homework done on time without procrastinating. During tests, I make sure to read through every questioncarefully and double check my work. With that level of discipline, I'm confident I can succeed academically at university.There will still definitely be some struggles though. I can imagine pulling multiple all-nighters to cram for big exams or finish major assignments. Choosing my class schedule each semester will probably be really stressful too since I'll want to take a million different interesting courses! And let's not forget about money...from what my parents tell me, university is crazy expensive. I'll likely have to take out student loans and spend years after graduating paying them back. Yikes.Despite those challenges, I still can't wait to experience university life. In my mind, it will be this wondrous place of intellectual freedom and personal growth. A place where I can explore my passions, discover new ones, and really figure out who I am and what I want to do with my life. How incredible is that?!I have so many big dreams for my future university days. I envision myself being a well-rounded student who doesexcellently in all my classes while still having an active social life. I'll join tons of clubs and organizations that align with my varied interests. Student government, debate team,photography club, martial arts, you name it! I want to push myself outside my comfort zone and try new experiences.Eventually after 4 amazing years on campus, I'll have to graduate. That will be such a bittersweet moment...I'll be thrilled to have finally earned my bachelor's degree, but so sad to leave that special community behind. Although I'm sure we'll have had plenty of wild school traditions and hijinks to go out with a bang!Then it will be off to start my career and get settled into "real" adult life in the working world. Thanks to my well-rounded university experience though, I'll be prepared to take on any challenge. Maybe I'll get a job right away or maybe I'll continue my education even further with graduate school. No matter what though, I know those university years will have equipped me with invaluable critical thinking abilities, problem-solving skills,real-world experience, and the drive to chase after my wildest dreams.University is still a long way off for me, but it's never too early to start getting excited! Even just imagining what that level of higher education will be like fills me with hope and determination. I know if I stay dedicated to doing well in school, getting outstanding grades, and exploring lots of extracurriculars,I'll be able to make it to the college of my dreams oneday. Then the real fun will begin! I can't wait.篇3My Awesome Future College LifeHey there! I'm just a kid in elementary school, but I've been dreaming about what my future college life will be like. It's going to be so cool and exciting! Let me tell you all about it.First off, I can't wait to move out of my parents' house and live on my own in a dorm room. No more having to share a bedroom with my annoying little brother! I'll have my own space, and I can decorate it however I want. I'm thinking about putting up tons of posters of my favorite superheroes and video game characters. Maybe I'll even get a lava lamp or one of those cool fiber-optic lights!Speaking of video games, I'll finally have all the time in the world to play as much as I want. No more nagging from Mom about finishing my homework or chores first. I'll just kick back, relax, and game all day if I feel like it. Of course, I'll still need to study and go to classes and stuff, but I'll have way more free time than I do now.And the classes themselves are going to be so much fun! No more boring lessons about multiplication tables or state capitals. In college, I'll get to learn about all sorts of cool and interesting things like rocket science, ancient civilizations, and maybe even how to make video games! I can't wait to meet all the professors too. I bet they'll be way nicer and more fun than my elementary school teachers.Another thing I'm really looking forward to is making new friends from all over the world. In elementary school, everyone is just from the same boring town, but in college, there will be people from different countries and cultures. I can't wait to swap stories and learn about their traditions and customs. Who knows, maybe I'll even pick up a few words in a new language!Oh, and let's not forget about the food! I've heard that college dining halls have all-you-can-eat buffets with every kind of food you can imagine. Pizza, burgers, ice cream sundaes – you name it, they'll have it. No more having to eat whatever my mom cooks for dinner. I can load up my plate with all my favorite treats!I know that college will also involve a lot of hard work and studying, but that's okay. I'm ready to buckle down and hit the books when I need to. After all, I want to get a great education soI can land my dream job one day. Maybe I'll become a video game designer, a scientist, or even an astronaut! The possibilities are endless.Overall, I can't wait for my awesome future college life to begin. It's going to be an incredible adventure filled with new experiences, new friends, and new opportunities for growth and learning. Sure, it might be a little bit scary leaving home and venturing out into the world on my own. But I know it's all part of growing up and becoming an independent adult.So bring it on, college! I'll be ready for you in a few years. Just you wait and see – I'm going to make the most of every single moment and have the time of my life. It's going to be epic!篇4My Dream of College LifeHi there! My name is Timmy, and I'm a third-grader at Sunny Meadows Elementary School. Today, I want to share my thoughts and dreams about what college life will be like in the future. I know I'm still pretty young, but I've been thinking a lot about it lately, and I have some big ideas!First off, I think college campuses in the future will be like these huge, high-tech wonderlands. Imagine buildings made of shiny metal and glass, with solar panels and wind turbines everywhere, providing clean energy for the whole campus. And instead of having to walk or ride bikes to get around, we'll have these cool little hover-scooters that zip us from one class to the next. How awesome would that be?Speaking of classes, I bet they'll be so much more fun and interactive than the ones we have now. Sure, we'll still need to learn stuff like math, science, and history, but it'll be way more hands-on and exciting. For example, in science class, we might take virtual reality field trips to explore the depths of the ocean or the surface of Mars. And in history class, we could use holographic projectors to reenact famous battles or meet historical figures face-to-face (well, sort of!).But it won't just be about the fancy gadgets and gizmos. I think college in the future will also focus a lot more on developing our creativity and problem-solving skills. We'll have classes where we get to design and build our own inventions, like robots or eco-friendly cars. Or we might work in teams to come up with solutions for real-world challenges, like finding ways to clean up the ocean or stop climate change.And you know what else would be really cool? If colleges had these massive, state-of-the-art maker spaces where we could tinker and experiment with all sorts of materials and tools. Imagine having access to 3D printers, laser cutters, and even mini factories to bring our ideas to life! We could start our own businesses right on campus, selling our creations to people all over the world.And let's not forget about the food! I'm hoping college cafeterias in the future will have these amazing, futuristic food replicators that can whip up any meal you can imagine – from piping hot pizzas to delicious, nutrient-packed smoothies – in just a matter of seconds. No more waiting in line for hours or eating boring, mushy cafeteria food!Well, that's about all I have to say for now. I hope you enjoyed my little essay, and I can't wait to see what the future holds for higher education. Who knows, maybe some of my wild ideas will come true! Only time will tell. Until then, I'd better get back to my homework. Math class awaits, and I don't want to be late!篇5My Future College LifeHi there! My name is Timmy and I'm 10 years old. I'm in the 5th grade and I love school, especially science class. We just learned about colleges and universities, and now I can't wait to go to college someday! I've been dreaming about what my college life will be like. Here's my vision of the ideal college experience in the future:To start, the campus will be absolutely huge! Like, bigger than the largest mall you've ever seen. The buildings will be shiny and modern, with cool architecture. Maybe some of them will even be shaped like pyramids or spheres instead of boring rectangles. The grounds will be beautiful, with gardens, ponds, fountains and plenty of trees and green spaces to hang out.Instead of chalkboards, every classroom will have massive TV screens covering the walls. No more tiny desk combo things - we'll have big, comfy chairs to sit in. And get this - we won't need to carry books or notebooks because every student will have a super thin, flexible computer screen about the size of a poster that weighs practically nothing. Maybe they'll even be holographic displays? That would be amazing!Classes will be way more interactive than just listening to lectures. With virtual reality headsets, we could actually experience things instead of just reading about them. Like for ahistory class, we could virtually walk through ancient Rome or the American Revolution battlefields. How cool would that be? Or in an anatomy class, we could explore a 3D model of the human body from the inside out. So much better than those old, smelly plastic models they have now!Speaking of technology, dorm rooms will be straight out of a sci-fi movie. Rooms could use smart walls and floors that shift into different conformations for studying, sleeping, or hanging out. You could make your room look like pretty much anything with configurable lighting, wall projections, and adjustable furniture. And of course, rooms would be voice controlled with AI assistants to manage settings, schedule, pulling up info, etc. No more fighting over temperature or leaving a mess!But college won't just be about studying. There will be so many awesome things to do on future campuses! I'm picturing giant rec centers with crazy virtual reality gaming arenas, hologrid sports simulators, anti-gravity dodgeball courts, you name it. And the main student center will be like an entire mall and amusement park combined, with shopping, restaurants, movies, mini golf, laser tag, and who knows what other fun stuff by then.The food in the dining halls will be out of this world too. Not just boring pizza and burgers like today. With advanced 3D food printers and molecular gastronomy, cafeterias could create wild gourmet dishes from any cuisine that are also optimized to be healthy and energizing for students. I'm dreaming of things like teriyaki dinosaur nuggets, breakfast banana split sundaes, or zesty rainbow nacho pyramids! And of course, it would all be included at no extra cost with your campus living plan.I can't wait to join lots of clubs and activities too. Like maybea zero-g acrobatics squad, an interstellar Quidditch team, or a competitive video gaming league. It would be so fun to get really good at something unique like that. And I've also thought about joining a band and playing real concerts around campus. Can you imagine being in a legit rock band when you're like 19 or 20 years old? That's basically a teenage dream come true!Living on campus will be like a year-round summer camp too. On nice days, everyone could hang out on the grassy quad, playing robot frisbee or just cloud gazing. And the campus might have a whole private beach and lazy river for weekends too. At night, there could be outdoor movie nights, stargazing in the observatory, raves/dance parties, bonfires and s'mores, or evencamping out in virtual campgrounds. So much better than being cooped up in a dorm all night.And the best part? No parents or curfews! As long as we go to classes and don't make too much trouble, we'll basically be free to do whatever we want. Stay up all night gaming, eat ice cream for every meal, dye your hair bright purple - you name it! No one can stop us because we'll finally be real adults. Well, except the robot proctors might enforce some rules so we don't go too crazy.I'm sure college in the future will be extremely high-tech, but also way more fun and freedom than today. Just thinking about it makes me never want to graduate elementary school! Although I guess if it's really that amazing, I probably wouldn't mind being in college forever. At least until I'm like 30 years old or so. Anyway, those are my hopes for the ideal futuristic university experience. I can't wait to see how my dreams turn out when it's finally my turn! Okay, back to studying so I can make that happen. Catch you later!篇6My Big Plans for University LifeI can't wait until I'm old enough to go to university! University seems like such an exciting adventure. I've heard so many amazing things about it from my older cousins and siblings. It will be a whole new world compared to living at home with my parents and going to my little elementary school. I have such big dreams and plans for what university life will be like!First off, I'm really looking forward to living in the dorms or residence halls on campus. How cool would it be to have my own little room and share a bathroom and common area with other students? We could stay up late every night talking, studying, eating snacks, and having fun. During the day, we'd all go to our different classes and then come back "home" to the dorms. The dining halls sound awesome too - you can eat whatever you want, whenever you want! No more being forced to eat vegetables I don't like.I hope I get a really fun and friendly roommate who becomes my best friend. We'd do everything together - go to parties, join clubs, pull all-nighters cramming for exams. My cousins say dorm life is where you make memories that last forever. Of course, I'd go home to visit my parents on holidays and breaks. But the rest of the time, I'd be living that independent university lifestyle!Speaking of classes, I can't wait to take courses on the super interesting topics they never teach us in elementary school. I'm talking about bizarre stuff like philosophy, astronomy, ancient languages, and who knows what else! No more basic reading, writing, and arithmetic. We'll be debating life's biggest questions and unlocking the mysteries of the universe. I'll finally be learning about things I'm genuinely curious about instead of boring busywork.And the professors all seem so cool and smart. They literally get paid just to think amazing thoughts and share their genius with students like me. I can't wait to pick some legendary professors' brains during their office hours and hear their wildest ideas. I'll be right there in the front row, soaking up every last mind-blowing fact from the masters. No more condescending teachers talking down to me - just professors respecting and engaging with me as a young scholar.Outside of class, university has an endless array of clubs, organizations, and activities to explore. I can't decide what I'll do first - join the rockclimbing club, write for the student newspaper, start a band with friends in the music hall, or all of the above! There are so many new skills to pick up and interests to discover. Maybe I'll even play an awesome sport for my university andbecome a star athlete. This is finally my chance to really find my passions and dive in 100%.And let's not forget about the awesome parties and social scene at university! Endless hangouts, meetups, concerts, and fun events every single night of the week. My cousins showed me pics of the massive football stadiums, rec centers with movie nights, comedy shows, and festivals happening all the time on campus. No more lame celebrations with family friends doing magic tricks for kids. This is the start of my young adult social life! Who knows how many lifelong friends and maybe even a boyfriend or girlfriend I'll meet through these crazy events?I can't even decide yet what I'll major in! There are so many intriguing options to choose from. Maybe computer science and coding? Or philosophy and literature? Economics and business? Marine biology? Psychology and criminal investigations? I'll take a wide variety of classes my first couple years to explore different fields before picking my concentration. I'm keeping an open mind because I know university will expose me to all kinds of new interests I may want to pursue.Well, I know it's still several years away until I'll actually be at university. But I can't stop daydreaming about it! It symbolizes the start of true independence and the adult life I've been soeagerly awaiting. My parents better start preparing now, because after high school, I'll be ready to fly the nest and soak up every last precious moment of the real university experience!。

用英语介绍最喜欢的课程作文大学

用英语介绍最喜欢的课程作文大学全文共6篇示例，供读者参考篇1My Favorite Class at UniversityHi there! My name is Timmy and I'm 8 years old. I may be just a kid, but I already know what I want to study when I grow up and go to university. There's this one class that I'm super excited about - it's my total favorite! Let me tell you all about it.The class is called "Underwater Basket Weaving 101" and it's exactly what it sounds like - you learn how to weave baskets while underwater! How cool is that? I mean, basket weaving is neat and all, but doing it underwater just makes it way more fun and adventurous.In the class, you start out on dry land to get the basics down. The professor, who everyone calls "Professor Kelp" because he looks like a piece of kelp with his long green hair and beard, teaches you the different weaving patterns and materials you can use. My favorite materials are colored reeds because they're bright and cheerful.Once you know the fundamentals, it's time for the real fun - you get to suit up and head into the university's gigantic indoor swimming pool for your underwater basket weaving training! The pool has this really awesome underwater classroom with desks and stools tied down to the bottom. You wear a scuba suit and oxygen tanks so you can breathe while fully submerged.Professor Kelp gives lessons down there by writing on a special underwater whiteboard and demonstrating basket weaving techniques. At first, it's pretty tricky trying to weave while holding your breath. But after a few classes, you get the hang of taking breaths from your oxygen tank between weaves. It's just like breathing normally, but underwater!The best part of the class is going on the underwater field trips. Professor Kelp will have the whole class dive down to the bottom of a lake or the ocean and we'll spend hours weaving baskets among the fish, coral, and plants. One time, we even had a friendly dolphin swim by and check out what we were making! I waved at it with my reed basket and it waved back with its flipper. So cool!I just love being in the underwater classroom. The filtered sunlight shines through the water in beams and everything has this peaceful, calming bluish tint to it. You can hear whale callsand bubbles faintly in the distance as you sit concentrating on your basket pattern. It's like entering a whole other world.After each field trip, we all get to keep the baskets we made. I've already filled up my room at home with dozens of colorful reed baskets I wove with my own two hands (well, with oxygen tank assistance at least!). My parents use them to hold everything from fruits to toys to socks. Sometimes I'll weave a special basket as a gift for their birthday or other holiday.I know underwater basket weaving may sound kind of silly or weird, but I absolutely love it. It combines so many of my favorite things - being in the water, making crafts, going on adventures, and hanging out with my friends. Just thinking about being in that tranquil underwater classroom puts a big smile on my face.I try to practice basket weaving at my bathtub at home, but it's just not the same as doing it for real submerged in a pool or lake. I have to hold my breath the entire time, which gets kind of tough after a while. I can't wait until I'm older so I can finally get scuba certified and take the class for real at university! It's definitely going to be my major.Well, that's my favorite university class - Underwater Basket Weaving 101. I may be a kid now, but I'm counting down the days until I can enroll. To me, there's nothing better than thefeeling of immersing yourself in the underwater world and zoning out while making a beautiful woven basket. It's just so peaceful and fun!If you're considering university classes too, you have to put underwater basket weaving at the top of your list. Who knows, maybe we'll be classmates one day! We can weave baskets together and befriend the local sea turtles. It'll be a underwater basket weaving party! Yeah, I totally can't wait.篇2My Favorite Subject at UniversityHi everyone! My name is Timmy and I'm going to tell you all about my favorite subject that I'm studying at university. Get ready because this is going to be super exciting!The subject I love the most is science. I know what you're thinking - "Ugh, science is so boring with all those big words and complicated stuff." But trust me, it's actually the coolest thing ever once you get into it!In my science classes, we get to learn about everything from the tiniest atoms to the biggest stars in the universe. It's like getting a backstage pass to how the entire world works. We evenget to do lots of fun experiments and projects to see science in action.One of my favorite experiments we did was making little rockets out of plastic bottles and seeing how high we could launch them by putting a special mixture inside. I made mine bright green and it flew so high into the sky before coming back down. It was epic!Another awesome thing about science is that there's always something new to discover. The professors are like scientists themselves, constantly studying and researching to uncover more secrets about our world. Sometimes they'll even let us join in on their science adventures as assistants. How cool is that?In biology, which is the study of living things, we get to look at plants, animals, and even human bodies up close. One time, we got to dissect a frog and see all its organs and body parts. It was a little gross, but fascinating at the same time! We also get to go on field trips to parks, forests, and museums to learn about different environments and ecosystems.Then in chemistry, we learn how everything is made up of tiny particles called atoms and molecules. We mix up colorful chemicals in test tubes and see how they react with each other. Some experiments even make cool effects like smoke or smallexplosions. Don't worry, it's totally safe when you follow the proper steps!My favorite part of chemistry has to be studying the periodic table though. It's like a awesome cheat sheet that lists out all 118 known elements in the entire universe. The table is actually super organized with different colors and symbols that give you hints about each element. Memorizing the periodic table is like learning a secret code that lets you understand the building blocks of absolutely everything.In physics, we study the rules of how things move, like gravity, force, energy, and motion. This part gets a bit more mathy withformulas and calculations, but it's worth it to learn mind-blowing concepts. Like did you know that if you shoot something straight up into the air, not counting air resistance, it will fall back down at the same speed regardless of how heavy or light it is? Isn't that wild?We even get to build simple machines like levers, pulleys, and inclined planes to see these physics laws in action. Once, we had a contest to see whose stopping barrier could best protect a raw egg from breaking when dropped. I built a crater-shaped foam cup and it worked like a charm!My favorite physicist that we learned about has to be Albert Einstein though. This dude basically rewrote the rules of physics with his theory of relativity. He showed how space and time are wonky and actually bend depending on how fast you're moving. My brain still hurts a little trying to understand it all. Einstein was definitely a super genius!Astronomy is another awesome branch of science that looks at stars, planets, galaxies, black holes, and everything else in outer space. We get to go to the university's observatory and look through massive telescopes to see real cosmic wonders. One night, I spotted Saturn and its beautiful rings. It was one of the coolest things I've ever seen!Learning about how stars are born, live, and eventually die is fascinating. Stars are basically huge nuclear reactors in space that fuse atoms together and release mind-boggling amounts of energy. I can't get enough of stuff like neutron stars, supernovas, and the mystery of black holes.I'm also obsessed with space exploration and all the incredible technologies that make it possible. We've studied the history of rocket science, satellites, landers, rovers, and of course the huge milestone of landing on the Moon back in 1969. I haveso much respect for the brave astronauts who risk their lives to explore the great unknown.Speaking of the Moon, I can't wait until we eventually send humans to Mars! Just imagining what it would be like to walk on another planet is so exhilarating. Hopefully in my lifetime we'll make even more space breakthroughs like establishing Moon bases, mining asteroids, visiting the moons of other planets, and who knows - maybe even finding signs of extraterrestrial life somewhere!No matter how advanced our knowledge gets though, the universe always has more surprises waiting to be uncovered. That's what makes science so exciting to me - the endless frontier of mysteries still left to be solved. Black holes, dark matter, other dimensions...there's a whole wonderful weirdness waiting for us to explore.I could keep going on and on about why I love science so much, but I'll wrap it up before your brain explodes. Studying science at university is like going on the greatest adventure of unraveling the deepest secrets of our cosmos. It exercises my mind while constantly filling me with awe and curiosity about the world.I know for sure that I want to become a scientist when I grow up so I can spend my life discovering and sharing new knowledge. Who knows, maybe I'll even make the nextgame-changing breakthrough that changes everything we thought we knew! The possibilities are endless when you follow the path of science. Thanks for reading, and happy exploring!篇3My Favorite ClassHey there! My name is Tommy and I'm in the 5th grade. Today I want to tell you all about my absolute favorite class in school. Can you guess what it is? It's science class!Science is just the coolest thing ever. We get to learn about how the whole universe works - from the tiniest atoms to the biggest stars and galaxies. It's like a big mystery that scientists are trying to solve piece by piece. And in science class, we get to be mini scientists ourselves and explore all kinds of amazing things.Our science teacher, Mr. Newton, makes every lesson fun and exciting. He's always doing these crazy experiments that make our jaws drop. Like this one time, he dropped a bunch of bouncy balls from different heights to show us about gravity andacceleration. We got to predict which balls would bounce higher and then watch as they went flying everywhere. It was total chaos but in a good way!Another time, Mr. Newton brought in a van de graaff generator, which is this huge metal sphere thing that makes your hair stick straight up from static electricity. He had us all line up and touch it one by one. When it was my turn, I thought I was going to get electrocuted or something. But instead, my hair just went POOF and stood straight up like I stuck a balloon to my head. Everybody cracked up laughing at how goofy I looked. Mr. Newton is the best for letting us do such weird but awesome experiments.But we don't just mess around all period. We actually learn some pretty cool stuff too. Like last semester, we studied outer space and the solar system. Did you know there are over 100 billion galaxies in the universe? And our Milky Way galaxy has over 200 billion stars in it? That's billions with a B! My mind was totally blown by numbers that huge.We got to make scale models of the planets out of styrofoam and paint to see how big (or tiny) each one is compared to the others. Jupiter ended up being a massive篇4My Favorite Class at UniversityHi friends! Today I want to tell you all about my absolute favorite class that I'm taking at university. It's so much fun and I learn such cool things. The class is called Computer Science 101 and it's all about computers and coding and building apps and games and websites and robots and all that awesome techy stuff!In Computer Science, we get to use these really neat machines called computers. They are like super smart calculators that can do way more than just math. With code, which is like a special language that computers understand, you can tell the computer to do all kinds of amazing things. It's like giving the computer instructions, kind of like how your parents give you instructions sometimes, except computers are really good at following the instructions exactly.One of the first things we learned was how to build basic websites. Websites are like cool online places that you can visit from any computer that's connected to the internet. We used a programming language called HTML to make the website structure, kind of like building with virtual Lego bricks. Then weused another language called CSS to make the website look pretty with different colors, fonts, and layouts. Finally, we added some JavaScript to make the website interactive and do things like animations when you click on stuff. It was so awesome seeing my website come to life!After that, we started learning Python, which is a really popular programming language. With Python, you can build all sorts of apps and games and even control robots! We've made simple games like Tic-Tac-Toe, Hangman, and even a version of Super Mario Bros. It's so satisfying when your code works and you can play your own game that you built from scratch. Sometimes the code has bugs and doesn't work at first, but our professor shows us how to find and fix the errors. It's like being a code detective!More recently, we've been learning about algorithms, which are kind of like step-by-step recipes that tell the computer how to solve a problem or complete a task. Some algorithms are used to sort and organize data, while others are for things like finding the shortest path between places on a map. It's like math and logic puzzles, but code-ified! I really enjoy wrestling with these algorithmic challenges and feeling super smart when I figure them out.Another awesome part of the class is when we get to work with tiny computers called microcontrollers. They're like tiny brains that you can code to perform specific functions. We've wired them up with sensors, motors, lights and more to make all kinds of cool gadgets and gizmos. One time I made a little robot that could follow a line on the floor using light sensors. Another time I made a game where you had to flip a switch and catch a falling ball in a cup. It's like electrician work meets programming!What I love most about Computer Science is that it combines logic, problem solving, creativity, and the power to build such useful and fun things from scratch. Sure, it can be frustrating when my code has bugs and doesn't work at first. But finally getting it right and seeing my program run perfectly is such an amazing feeling of accomplishment. It's like a puzzle that really makes my brain work hard.The professor is great too. He's super passionate about coding and technology and always has interesting stories to share about computer history and the amazing things people have built with code. Sometimes he goes a little over my head with the advanced concepts, but he's really good about explaining things in simple terms too. And unlike some teachers who get annoyed with questions, he really wants us tounderstand and encourages us to ask as many questions as we need.I absolutely love Computer Science class! Maybe when I grow up, I can get a job as a awesome coder and programmer. I could build video games or apps that help make people's lives better and easier. Maybe I'll even become the next Mark Zuckerberg or Bill Gates and start a huge tech company of my own someday. Or who knows, I could use my coding skills to program robots to explore other planets! The possibilities are endless when you know how to computer program. For now, I'm just having a blast learning and building cool programs in my favorite class. Coding is the best!篇5My Favorite Class: English!Hey there! My name is Tommy and I'm in the 5th grade. Today I want to tell you all about my absolute favorite class - English! I just love learning about words, reading cool stories, and writing my own tales. English is super fun and interesting. Let me explain why I like it so much!First off, I really enjoy reading in English class. We get to read all kinds of awesome books and stories! Some of them arefictional tales about brave knights, friendly dragons, or kids going on crazy adventures. Other stories are real accounts about historical events or the lives of famous people. No matter what we're reading, the books always keep me on the edge of my seat, desperate to find out what happens next.Our teacher Mrs. Anderson has a special talent for picking the most gripping, page-turning books. Whenever she introduces a new book to the class, I get really excited. I just can't wait to crack it open and start reading! Sometimes I even sneak ahead and read portions at home because I get too impatient to find out what happens. Oops, don't tell Mrs. Anderson!Reading the books is great, but you know what's even better? Discussing them as a class! Mrs. Anderson asks us lots of engaging questions to analyze the stories. Things like "Why do you think the character made that choice?" or "What lesson can we learn from this event?" It's fun sharing my thoughts and hearing my classmates' perspectives. Their ideas help me understand the books on a deeper level.Another reason I love English is because of all the creative writing we get to do. We've worked on all sorts of fun writing assignments - short stories, poems, comics, you name it! I really enjoy flexing my imagination muscles to come up with wackycharacters, interesting plots, and descriptive settings. Writing stories is like bringing new worlds to life with nothing but some words on a page. How crazy is that?My favorite writing projects are definitely the long ones where we work for weeks or even months crafting an entire book. I'll never forget the sense of pride and accomplishment I felt creating and illustrating my very own 100-page fantasy novel last year. All my hard work had finally paid off! I can't wait to become a published author someday.Of course, my English skills wouldn't be nearly as good without Mrs. Anderson's excellent teaching. She is a master at explaining concepts in a simple, easy-to-understand way. Whenever I get confused about grammar rules, vocabulary words, or writing strategies, she always knows how to clarify things so they make perfect sense. Mrs. Anderson also makes learning feel like a fun game instead of boring work.For example, when studying new vocabulary, she has us play Charades or Pictionary to act out or draw the words' meanings instead of just memorizing definitions from a list. Games like that make it much easier to remember what alligator or interrogate mean! We also sometimes have "Word Sneak" competitions, where we try to inconspicuously incorporate as many newvocabulary words as possible into our casual conversations. Silly games like those make vocabulary practice a total blast.Mrs. Anderson's passion for English is truly inspiring. You can tell she absolutely loves reading, writing, and teaching by the way her eyes light up during class. Her energy and enthusiasm are contagious! Whenever she reads a brilliant passage from a novel using different voices for each character, I can't help but become even more invested in the story. And when she shares creative writing tips or grammatical lessons, it's hard not to get excited about improving my own skills.In fact, Mrs. Anderson's obvious affection for the English language and literature is what initially sparked my interest in the subject. At the beginning of the school year, I'll admit that I found English kind of boring. Reading and writing always seemed like a chore before. But after witnessing Mrs. Anderson's genuine love for it, I started to view English in a whole new light. If this subject could captivate someone so much, maybe it was actually pretty fascinating!Well, I'm certainly glad I gave English a chance, because it ended up being the coolest, most engaging class ever! Reading, writing, vocabulary, grammar - I honestly get excited for every aspect of English nowadays. The subject allows me to exploreendless imaginative worlds while also helping me become a stronger communicator. What's not to love?Not only is English extremely fun and interesting, but it's also one of the most important, useful classes I take. Think about it - we use language literally every single day to interact with others, learn new things, express our thoughts and feelings, and so much more. Being able to read, write, and communicate well in English is absolutely crucial for success in life. The skills I'm developing now will continue benefiting me forever.That's why English is hands-down my favorite school subject. It's endlessly engaging, lets me get creative, and teaches me abilities I'll need throughout my entire life. Not to mention, my English teacher Mrs. Anderson makes every class a total joy with her passion and entertaining lessons. Reading, writing, and learning about the English language is just plain awesome!So there you have it - my enthusiastic ode to English class. Looking back on everything I've written here, I feel like I could keep gushing about the subject forever. But I'll spare you any more of my ramblings for now. Just know that English is amazing and if it's not your favorite class already, it definitely should be! Thanks for reading, and be sure to keep practicing those English skills. Adios!篇6My Most Favorite Subject in Big Kid SchoolHi everyone! My name is Tommy and I'm 8 years old. I can't wait until I'm older and get to go to a big university like my big brother. He's studying at a huge school right now and tells me all about the cool classes he gets to take. His favorite class sounds like the most fun ever - I really want to take it when I'm older too!The class my brother loves is called "English Literature" and it's all about reading awesome stories and books. How neat is that? Getting to just read books for your schoolwork? Sign me up!In English Literature, you get to read classic books that people have loved for hundreds of years. My brother said they just finished reading Romeo and Juliet by William Shakespeare. That one is a tragic love story about two young people from feuding families who fall in love. Even though I'm just a kid, I can understand loving someone you're not allowed to be with. Like when I had a huge crush on Samantha in my 2nd grade class but she liked Billy instead. Heartbreaking!They also read The Great Gatsby which is considered one of the greatest novels of all time. It's about super rich people livingin New York in the 1920s going to parties and having romantic troubles. Doesn't that sound intriguing? I'd love to read about crazy rich people's lives! My brother said there were lots of cool words and phrases in that book that he'd never heard before too. Learning new vocabulary is always fun.But the best part about English Literature is apparently getting to analyze and discuss all the hidden meanings and messages in the books. See, authors often use symbolism and metaphors to express deeper ideas beyond just the surface story. How cool is it to get to think critically about that kind of stuff? It's like solving a mystery or puzzle with each book you read. My brother said they spent weeks discussing what the green light across the bay represented in The Great Gatsby. Still not sure if they ever fully figured it out!In English Lit, you also learn about the time period and background that the author was writing in. That historical and cultural context is important for fully understanding the books. Like how The Great Gatsby represented the narcisissm and empty pursuit of wealth in America in the 1920s. Or how Shakespeare's plays had hidden meanings criticizing the monarchy and society back in the 1600s when he wrote them. Very subversive!Another thing I can't wait to do is get to write my own analytical essays and papers about the books. How fun does that sound? Getting。

想做还没做的事情英语作文带翻来

想做还没做的事情英语作文带翻来全文共6篇示例，供读者参考篇1There are so many things I want to do, but haven't had the chance to do yet. Some of them are big dreams, while others are small goals. Let me tell you about a few of them.One thing I really want to do is learn how to swim. I've seen people swimming in pools and lakes, and it looks like so much fun! Splashing around in the water, diving underneath the surface, and just feeling weightless seems incredibly freeing. My parents have promised to enroll me in swimming lessons this summer, so I'm keeping my fingers crossed that I'll finally get to learn.Another thing on my wishlist is to climb a tall mountain. I love being outdoors and surrounded by nature. The idea of standing at the peak of a massive mountain, looking out over the world below, gives me a thrill. Of course, I know mountain climbing can be dangerous, so I'll have to wait until I'm older and properly trained. But I can dream about it for now!I also really want to learn how to play the guitar. There's just something so cool about being able to make music with your own hands. I have a couple of friends who play, and they're always surrounded by people who want to listen and sing along. Playing an instrument seems like it would be a lot of fun and a great way to meet new people. Maybe I can convince my parents to let me take guitar lessons for my next birthday.One goal that might seem a bit silly is that I want to stay up all night long, just once. I've tried to do it before, but I always end up falling asleep around midnight or 1 AM. There's something exciting about the idea of being awake when the rest of the world is asleep. Of course, I know it's not really healthy to do that too often, but I think it would be fun as a one-time adventure.If I'm being totally honest, one of the biggest things I want to do is go on a trip all by myself. Not forever, of course, but just a short solo trip to somewhere new and exciting. I love traveling with my family, but there's something appealing about the idea of making my own decisions about where to go, what to see, and what to eat. It would be a chance to prove to myself and my parents that I'm mature and responsible enough to handle being on my own for a little while. Maybe when I'm a bit older, they'll let me go on a small trip, just for a night or two.Those are just a few of the many things on my "want to do" list. Who knows, maybe by this time next year, I'll have crossed off learning to swim, playing the guitar, and even going on that solo trip! A person can dream, right? For now, I'll just have to be patient and keep working towards making those dreams into realities.There are so many amazing experiences just waiting to be had. I can't wait to get started on tackling this list!【想做还没做的事情英语作文带翻译】有太多我想做但还没有机会做的事情了。

红移z≈2极亮红外星系的研究进展

红移z≈2极亮红外星系的研究进展方官文;林泽森;孔旭【摘要】极亮红外星系(ULIRGs)是指红外(IR,8～1 000 μm)光度LIR＞1012 L☉的一类星系.研究表明,红移z≈2处极亮红外星系是大质量(M*＞1011 M☉)、富尘埃和强恒星形成(大于100 M☉·a-1)的特殊星系.极亮红外星系可分成活动星系核起主导作用的源和恒星形成占主导的星系.恒星形成主导的源,中红外光谱有明显的多环芳香烃辐射;而活动星系核主导的星系,光谱呈现出幂律形式并有很强的硅线吸收.极亮红外星系的静止光学波段形态存在多样化,既有并合结构特征,又有椭圆形态.这类星系很可能是近邻大质量宁静星系的前身星系.介绍了红移z=2附近极亮红外星系的各种物理性质的研究进展,如形态和结构、光谱特征、成团性、尘埃分布和形成机制等,以及阐述了该领域未来的研究方向.%UltraLuminous InfraRed Galaxies (ULIRGs) are galaxies defined to have extremely high infrared (IR) luminosities (LIR ＞1012 L☉).Observations have shown that high-redshift ULIRGs are massive galaxies (M* ＞1011 M☉),with extremely high ratio of infrared to optical flux density (F24 μm/FR ＞ 1 000) and intensive star formation (100 ～1 000 M☉ · a-1).These objects are relatively rare at z ≈ 0,but their space density rapidly increase with look-back time and apparently peaks around z =2 ～ 3.Upon it's discovery,ULIRGs were suggested to be a feasible evolutionary phase towards the formation of local massive early-type galaxies.Their rest-frame optical morphologies show that high-redshift ULIRGs are a mixture of mergers or interacting systems,irregular galaxies,disks,and ellipticals.The morphological diversities of ULIRGs suggest that there are different formation processes for thesegalaxies.Merger processes between galaxies and disk instabilities play an important role in the formation and evolution of ULIRGs at high redshift.Mid-infrared (MIR) spectra of ULIRGs are observed with the Spitzer/IRS (InfraRed Spectrograph) instrument.For ULIRGs at z ≈ 2,major spectral features including the PAH (Polycyclic Aromatic Hydrocarbon) emission features at 7.7,8.6,and 11.3 μm and silicate absorption from 8 to 13 μm (peaking at 9.7 μm) fall in the observable wavelength range.ULIRGs can be divided into two types according to their MIR spectra.Objects with strong power-law continua are powered mainly by active galactic nuclei (AGNs),while those with a strong PAH emission are powered by intensive star formation.The clustering signal of ULIRGs roughly corresponds to a correlation length of r0 =7.40 h-1.Mpc for the full F24 μm ＞ 0.3 mJy sample.The clustering strength increases with luminosity,up to r0 =12.97 h-1.Mpc for F24 μm ＞ 0.6 mJy ULIRGs.Moreover,observations demonstrate that a median dust temperature is about 40 K for ULIRGs at z ≈ 2.【期刊名称】《天文学进展》【年(卷),期】2017(035)001【总页数】19页(P16-34)【关键词】高红移星系;星系观测;星系形态;星系光谱;星系成团性【作者】方官文;林泽森;孔旭【作者单位】大理大学天文与科技史研究所,大理671003;中国科学技术大学天文学系,合肥230026;中国科学院星系与宇宙学重点实验室,合肥230026;中国科学技术大学天文学系,合肥230026;中国科学院星系与宇宙学重点实验室,合肥230026【正文语种】中文【中图分类】P157.1相对于近邻星系，高红移 (特别是红移 z=2 附近)大质量星系的形成和演化研究也有着非常重要的意义。

中科院研究生院《固体物理》课程课件合集.pdf

X射线衍射
X射线衍射
X射线主要与电子云相互作用只考虑原子对X射线的弹性反射
晶面反射
相长干涉需要光程相等
bc ad dac bca
Bragg 把晶体对 X光的衍射当作由原子平面（晶面）的镜面反射，在满足镜面反射的衍射方向上，一个晶面内所有原子的散射波位相相同、相互叠加，形成相长干涉
晶体结构的探测
虽然点群和空间群理论以及晶格理论都是19世纪提出的，但直到1912年Laue发现了晶体X射线衍射现象之后才得以从实验上观测到晶体结构并证实了上述理论。
普通光学显微镜受分辨率的限制，无法观测原子排列，使用X光源，至今又没有可以使X光聚焦的透镜，所以只能依靠衍射现象来间接观测晶体中的原子排列。
这就是X射线衍射的劳厄条件；
可以证明劳厄条件和布拉格条件等价。
劳厄条件
k
k
G
h
k k Gh
k k
k
Gh
k
Ewald球
k k Gh
劳厄法
晶体取向固定，采用波长在 min 和max 之间的连续波长的X射线；
劳厄法
晶体取向固定，采用波长在 min 和max 之间的连续波长的X射线；
1.2
(nm )
eV 12
波长与晶格常数可比时，如波长 0.1nm 对应的能量 150 eV 。因此适合于晶体结构研究的是20~250eV的低能电子束。
电子带电，与原子相互作用强，穿透深度约几个原子层间距量级，因此低能电子衍射(Low Energy Electron Diffraction, LEED)主要用于晶体表面结构研究。
T (Rn ) (r ) (r Rn )
电子密度具有平移对称性

Parsec-Scale Images of Flat-Spectrum Radio Sources in Seyfert Galaxies

a rXiv:as tr o-ph/998255v123Aug1999Accepted –To appear in The Astrophysical Journal.Parsec-Scale Images of Flat-Spectrum Radio Sources in Seyfert Galaxies C.G.Mundell Department of Astronomy,University of Maryland,College Park,MD,20742,USA;A.S.Wilson 1Department of Astronomy,University of Maryland,College Park,MD,20742,USA;J.S.Ulvestad National Radio Astronomy Observatory,P.O.Box O,Socorro,NM,87801,USA;A.L.Roy 2National Radio Astronomy Observatory,P.O.Box O,Socorro,NM,87801,USA ABSTRACT We present high angular resolution (∼2mas)radio continuum observations of ﬁve Seyfert galaxies with ﬂat-spectrum radio nuclei,using the VLBA at 8.4GHz.The goal of the project is to test whether these ﬂat-spectrum cores represent thermal emission from the accretion disk,as inferred previously by Gallimore et al.for NGC 1068,or non-thermal,synchrotron self-absorbed emission,which is believed to be responsible for more powerful,ﬂat-spectrum nuclear sources in radio galaxies and quasars.In four sources (T0109−383,NGC 2110,NGC 5252,Mrk 926),the nuclear source is detected but unresolved by the VLBA,indicating brightness temperatures in excess of 108K and sizes,on average,less than 1pc.We argue that the radio emission is non-thermal and synchrotron self-absorbed in these galaxies,but Doppler boosting by relativistic outﬂows is not required.Synchrotron self-absorption brightness temperatures suggest intrinsic source sizes smaller than ∼0.05−0.2pc,for these four galaxies,the smallest of which corresponds to a light-crossing time of ∼60light days or 104gravitational radii for a 108M ⊙black hole.In one of these galaxies (NGC 2110),there is alsoextended(∼0.2pc)radio emission along the same direction as the400-pc scalejet seen with the VLA,suggesting that the extended emission comes from thebase of the jet.In another galaxy(NGC4388),theﬂat-spectrum nuclear sourceis undetected by the VLBA.We also present MERLIN and VLA observations ofthis galaxy and argue that the observed,ﬂat-spectrum,nuclear radio emissionrepresents optically thin,free-free radiation from dense thermal gas on scales≃0.4to a few pc.It is notable that the two Seyfert galaxies with detectedthermal nuclear radio emission(NGC1068and NGC4388)both have largeX-ray absorbing columns,suggesting that columns in excess of≃1024cm−2areneeded for such disks to be detectable.Subject headings:accretion disks—galaxies:active—galaxies:jets—galaxies:nuclei—galaxies:Seyfert1.IntroductionIt has become generally accepted that supermassive black holes(SBH)lie at the center of most,if not all,galaxies(e.g.,Richstone et al.,1998;van der Marel,1999),with some lying dormant and others being triggered into an active phase to produce active galactic nuclei(AGN)(e.g.,Haehnelt&Rees,1993;Silk&Rees,1998).The power source for this activity is thought to be accretion of material onto the SBH,with the infalling material forming an accretion disk which,depending on detailed conditions,then regulates the fueling rate(e.g.Narayan&Yi,1994;Kato,Fukue&Mineshige,1998;Blandford& Begelman,1998).The radius to which these accretion disks extend(and hence become more easily observable)is not well established,but current AGN uniﬁcation schemes advocate a geometrically thick and clumpy torus(e.g.Krolik&Begelman,1988;Krolik and Lepp, 1989;Pier&Krolik,1992)or warped thin disk(Miyoshi et al.,1995;Greenhill et al.,1995; Herrnstein,Greenhill&Moran,1996;Pringle,1996;Maloney,Begelman&Pringle,1996) which hides the nucleus when viewed edge-on.Our viewing angle with respect to the torus or disk is then responsible for the observed diﬀerences between narrow-line AGNs(e.g Seyfert2’s),in which our view of the nuclear broad-line region is obscured(edge-on view), and unobscured(pole-on view)broad-line AGNs(e.g.Seyfert1’s).Indirect evidence in support of such tori includes the discovery of broad lines in the polarized(hence scattered) light of Seyfert2s(Antonucci&Miller,1985;Tran,1995),sharp-edged bi-cones of ionized gas(e.g.,Wilson&Tsvetanov,1994)photo-ionized by anisotropic nuclear UV radiation (perhaps originating from the accretion disk and further collimated by the torus),large gas column densities(1023−25cm−2)to the nuclei of Seyfert2’s,inferred from photoelectricabsorption of soft X-rays(Turner et al.,1997)and strong mid-infrared emission in both Seyfert types(e.g.,Antonucci,1993;Alonso-Herrero,Ward&Kotilainen,1996).Recent,high-resolution studies at optical and radio wavelengths have begun to provide more direct evidence for‘nuclear’disks on size-scales ranging from the∼100-1000-pc diameter dusty disks imaged by HST(Jaﬀe et al.,1993;Ford et al.,1994;Carollo et al., 1997)and millimeter interferometry(Baker&Scoville,1998;Downes&Solomon,1998)to pc-scale disks inferred from HI and free-free absorption studies(Mundell et al.,1995;Carilli et al.,1998;Peck&Taylor,1998;Wilson et al.,1998;Taylor et al.,1999;Ulvestad,Wrobel &Carilli,1999),down to the0.25-pc warped,edge-on,Keplerian maser disk in NGC4258, imaged by the VLBA(Miyoshi et al.,1995,Greenhill et al.,1995;Herrnstein,et al.,1996).Theoretical work indicates that UV/X-ray radiation from the central engine can heat, ionize and evaporate the gas on the inner edge of the torus(Pier&Voit,1995;Balsara& Krolik,1993;Krolik&Lepp,1989).Indeed,simple Str¨o mgren sphere arguments suggest a radius for the ionized region of R(pc)=1.5(N⋆/1054s−1)1/3(n e/105cm−3)−2/3,where N⋆is the number of nuclear ionizing photons per second and n e is the electron density. Recalling the typical density n e∼105−6cm−3of the ionized disk in NGC1068(see below), we expect R∼0.3−1.5pc which is comparable to the tenths of pc to∼pc-scale resolutions achievable with the VLBA for nearby Seyferts.Recent high angular resolution VLBA radio observations of the archetypal Seyfert2galaxy,NGC1068,by Gallimore et al.(1997),have shown that emission from one of the radio components(‘S1’)may be associated with the inner,ionized edge of the torus.This radio component has aﬂat or rising(towards higher frequencies)spectrum,suggesting it contains the AGN,and a brightness temperature of up to4×106K;it is elongated perpendicular to the inner radio ejecta and extends over∼40 mas(3pc).The radiation mechanism may be free-free thermal emission(Gallimore et al., 1997),direct synchrotron emission(Roy et al.,1998)or Thomson scattering of a nuclear ﬂat-spectrum synchrotron self-absorbed radio core(itself not detected)by the electrons at the inner edges of the torus(Gallimore et al.,1997;Roy et al.,1998).This discovery highlights the possibility of using the VLBA to image the pc-scale disks or tori in other Seyfert galaxies.However,ﬂat-spectrum radio sources in AGNs often represent non-thermal synchrotron self-absorbed radio emission with a much higher brightness temperature(>108K)than is characteristic of component S1in NGC1068. High resolution radio observations are thus required to distinguish between the two emission processes.In the present paper,we report parsec-scale VLBA imaging ofﬁve Seyfert galaxies withﬂat-spectrum radio cores and hundred-pc scale,steep-spectrum,radio jets and lobes.Two of these galaxies also exhibit ionization cones with sharp,straight edges and axes aligned with the radio ejecta.Our goal is to determine whether theﬂat spectrumnuclear radio emission represents thermal emission from the accretion disk/obscuring torus or synchrotron self-absorbed emission from a compact radio core source.The paper is organized as follows;Sections2and3describe the sample selection, observations and reduction techniques whilst in Section4,the results of the study are presented.Section5discusses possible scenarios for the observed radio emission including direct non-thermal radiation from the AGN,emission from supernovae or supernova remnants produced in a starburst,or thermal emission from the accretion disk.The observed brightness temperatures are discussed in the context of the NGC1068result and comparison is made with other types of active nuclei such as radio galaxies,radio-loud and radio-quiet quasars.Section6summarizes the conclusions.Throughout,we assume H0=75km s−1Mpc−1and q0=0.5.2.Sample SelectionThe radio emission of Seyfert galaxies imaged at resolutions0.′′1–1′′almost always has the steep spectrum characteristic of optically thin synchrotron radiation.Flat spectrum cores are rare.In order to identify galaxies that may contain radio components similarto‘S1’in NGC1068,we have reviewed both published(e.g.,Ulvestad&Wilson,1989, and earlier papers in this series atλ6cm andλ20cm;Kukula et al.,1995at3.6cm)and unpublished(Wilson,Braatz&Dressel at3.6cm)VLA‘A’conﬁguration surveys and other interferometric studies(e.g.,Roy et al.,1994).In selecting candidate galaxies for VLBA observations,we used the following criteria:•The radio component that is coincident with the optical nucleus(the position of which is known to≈0.′′2accuracy–e.g.,Clements,1981,1983),has aﬂat spectrum(α≤0.4, S∝ν−α)between20cm and6cm or3.6cm with the VLA in‘A’conﬁguration.This component must also be unresolved in the VLA‘A’conﬁguration at2cm and/or3.6cm.•Theﬂux density of this component exceeds5mJy at3.6cm(for comparison,the total ﬂux density of component‘S1’in NGC1068at this wavelength is14mJy).•There is,in addition,extended,‘linear’(double,triple or jet-like),steep spectrum radio emission on the hundreds of parsecs–kiloparsec scales,or well-deﬁned,optical ionization cones.The reason for this last criterion is to deﬁne the axis of ejection of the radio components and thus the expected axis of the accretion disk.We found only six(excluding NGC1068)Seyfert galaxies that satisfy these three criteria in the entire sample of about130imaged in the‘A’conﬁguration.We omit one ofthem because of its unfavorable declination(–44◦),leavingﬁve for imaging with the VLBA. These galaxies are T0109−383,NGC2110,NGC4388,NGC5252and Mrk926.3.Observations and Reduction3.1.VLBA ObservationsThe observations were obtained with the10-element VLBA(Napier et al,1994)at8.4 GHz during observing runs in1997and1998,details of which are given in Table1.Dual circular polarizations(Right&Left)were recorded for all sources,and only the parallel hands(i.e.RR and LL)were correlated.T0109−383,NGC2110and Mrk926were recorded with a32-MHz bandwidth and two-bit sampling(8MHz per IF,4IFs,2polarizations)and NGC4388and NGC5252were recorded with a16-MHz bandwidth and two-bit sampling.The target sources are too weak to obtain estimates of the phase errors using standard VLBI self-calibration/imaging techniques(e.g.Walker,1995);instead the targets were observed in phase referencing mode,in which frequent observations of a nearby bright calibrator are interleaved with target scans and used for fringeﬁtting,which corrects the large phase errors,delays(phase variations as a function of frequency)and delay rates (phase variations as a function of time)present in the data(Beasley&Conway,1995). As described below,extending the coherence time in this way improves the signal-to-noise ratio and enables an image of the target source to be made,which can then be usedas a starting model for subsequent cycles of self-calibration.Target source plus phase calibrator cycle times are shown in Table1.This method is similar to that used on smaller, connected-element arrays,such as the VLA(known as‘phase calibration’),but is more problematic for VLBI due to larger and more rapidly varying phase errors.Rapid changes in the troposphere at8.4GHz therefore require short switching times to satisfy the condition that the change in atmospheric phase be less than a radian over the switching interval,thus enabling reliable phase connection,without2π-radian ambiguities,for successful imaging of the target source(Beasley&Conway,1995).In addition,less frequent observations were made of a bright calibrator(‘phase check’)source.Data editing and calibration followed standard methods(Greisen&Murphy,1998) and used the NRAO Astronomical Image Processing System(aips)(van Moorsel,Kemball &Greisen,1996).Amplitude scales were determined from standard VLBA antenna gain tables,maintained by NRAO staﬀ,and measurements of T sys made throughout the run. In addition,all data for source elevations below∼5◦were removed,and the antennas at Hancock(HN),and North Liberty(NL)were deleted from the NGC5252dataset as nofringes were detected to HN,and NL showed poor phase stability due to bad weather.The ﬁnal phase corrections,interpolated over time,were used as a guide for additional data editing.Despite short switching times between galaxy and phase calibrator,poor tropospheric conditions and uncertainty in the target source position prevented immediate imaging of the phase-referenced target sources using all the data.Observations of the‘phase check’source were therefore used to verify the quality of the phase referencing,before applying the phase corrections to the target sources,and to provide ancillary calibration such as manual pulse calibration and amplitude calibration checks.After imaging the phase calibrator to verify that the corrections derived from fringe ﬁtting were valid,phase,delay and rate corrections were applied to the‘check source’,from phase calibrator scans that were adjacent in time to the check source.Many baselines displayed poor phase coherence at some point in the observing run,preventing a coherent image of the source from being produced initially from the whole dataset.Instead,small time ranges(e.g.around1hour),within which the majority of antennas had less rapidly varying phases,were selected to be used in the initial stages of the imaging process.The ‘check’source,with calibration applied from the phase calibrator,was imaged for the selected small time range.The resultant image was then used as an input/starting model for subsequent cycles of self-calibration.This self-calibration process then enabled the remaining data to be fully calibrated and used to make aﬁnal image of the‘check’source. Theﬁnal structure,ﬂux and position of each‘check’source compared well with previously published images(e.g.Browne et al.,1998;Fey&Charlot,1997)and images produced from our data using self-calibration alone.This method provides an independent consistency check on the phase referencing,increasing our conﬁdence in the images of the target sources. Only one‘check’source(J0044-3530)was not successfully imaged due to insuﬃcient data (i.e.only3minutes at very low elevation).The target sources were then imaged using the same method,with natural and uniform data weighting.The uniformly weighted images (with robust parameter0-Briggs,1995)are shown in Figure1.The naturally weighted images,with more sensitivity to extended emission,were used to derive the brightness temperature limits to possible thermal emission from the program galaxies;these limits are ∼30%lower than those derived from the uniformly weighted images shown in this paper.The uncertainty in theﬂux scale is taken to be∼5%and is included in the total uncertainties inﬂux densities quoted in Table2.These errors were derived by adding,in quadrature,the5%amplitude scale error,the r.m.s.noise in theﬁnal image and the error in the Gaussianﬁtting.The accuracy of the target source positions is dominated by the uncertainty in theposition of the phase calibrators(∼0.4–14mas;see Table1).Additional positional errors, due to the transfer of phase corrections from the phase calibrator to the target source,are negligible due to the promixity of each calibrator to its target source.3.2.MERLIN observationsNGC4388was not detected by the present VLBA observations.We therefore obtained and analyzed MERLINλ6-cm(4.993-GHz)archival data for NGC4388,which was observed on7th December,1992with six antennas.Phase referencing was performed with regular observations of1215+113,interleaved throughout the observing run and3C286was used for ﬂux and bandpass calibration.Aﬂux of7.087Jy for3C286was adopted,assuming a total ﬂux density of7.382Jy(Baars et al.,1977)and correcting for MERLIN resolution eﬀects. After initial gain-elevation corrections and amplitude calibration using MERLIN software, the data were transferred to aips for all subsequent phase and amplitude calibration,data editing and imaging.Dual polarizations were recorded for a15-MHz bandwidth,centered at4.993GHz,but the right circular polarization data were removed due to instrumental problems,resulting in aﬁnal image of the left circular polarization only(Figure2).4.ResultsFiveﬂat-spectrum-core Seyferts,were observed with the VLBA at8.4GHz.Four of theﬁve sources were detected(T0109−383,NGC2110,NGC5252,Mrk926)and show compact,unresolved cores with brightness temperatures T B>108K,total luminosities at 8.4GHz of∼1021W Hz−1and sizes,on average,less than1pc.In addition to the core emission,NGC2110shows extended emission which may represent the inner parts of the radio jets,and NGC5252may be marginally extended(Figure1).NGC4388is not detected with the VLBA,but is detected at5GHz with MERLIN(Figure2).Weﬁnd no evidence for emission(to a3-σlimit of T B∼106K)extended perpendicular to the hundred-pc scale radio emission in T0109−383,NGC2110,NGC5252or Mrk926,as would be expected for emission from an accretion disk,but we discuss the possibility of thermal emission from NGC4388(Section5.4).The measured and derived properties of each source are listed in Table2,while more detailed properties of NGC2110and NGC4388are given in Tables3 and4respectively.The properties of each source are discussed more fully below.Distances are calculated assuming H0=75km s−1Mpc−1and q0=0.5,except for NGC4388which is assumed to be at the distance of the Virgo cluster,taken to be16Mpc.4.1.T0109−383T0109−383(NGC424)is a highly inclined(∼75◦)early-type((R)SB(r)0/a–de Vaucouleurs et al.1991)Seyfert galaxy at a distance of46.6Mpc.The nucleus ofT0109−383,originally classiﬁed as a Seyfert type2(Smith,1975),exhibits strong line emission from highly ionized species such as[Fe vii]λ5720,6086and[Fe x]λ6374(Fosbury &Sansom,1983;Penston et al.,1984).Analysis of the continuum emission from thefar IR to the far UV and decomposition of the Hα–[N ii]blend led Boisson&Durret (1986)to suggest a re-classiﬁcation of T0109−383to a Seyfert1.The recent discoveryof broad components to the Hαand Hβlines,along with emission from Fe ii,conﬁrms the type1classiﬁcation(Murayama et al.,1998).VLA images of the radio emissionat6and20cm,show the nuclear radio source to consist of an unresolved core with aﬂat spectrum(α206=0.17±0.07)betweenλ6andλ20cm,and a weaker,secondary,steep spectrum component≃1.′′4east of the core(Ulvestad&Wilson,1989).Similar radio structure is seen in the8.4-GHz VLA image(Braatz,Wilson&Dressel,unpublished), shown in Figure1,with the core spectrum remaining relativelyﬂat(α63.5=0.21)between6 and3.5cm(Morganti et al.,1999).The results of Gaussianﬁtting to the8.4-GHz VLBA image(Figure1),given in Table2,show the sub-pc scale nuclear emission to be unresolved, with a peak brightness of T B>8.1×108K,adopting a source size smaller than half of the beamsize.The peak and integrated8.4-GHz VLAﬂuxes for the core,10.4mJy beam−1 and11.2mJy respectively,are in excellent agreement with those measured from the VLBA image(Table2),indicating that little nuclear emission was missed by the VLBA.A similar peak brightness of10.4mJy beam−1is found in the3.5-cm ATCA image of Morganti et al. (1999),while their slightly higher integratedﬂux includes some of the emission≃1′′E and W of the nucleus(Ulvestad&Wilson,1989;Figure1).The excellent agreement between the nuclearλ3.6-cmﬂuxes in observations spanning∼six years indicates no signiﬁcant variability.In the VLBA image,we detected no extended emission in the N-S direction(as might be expected from a parsec-scale,thermal disk if the arcsec-scale,steep spectrum,E-W emission in the VLA image is interpreted as emission from nuclear ejecta)brighter than ∼1.3×106K(3σin the naturally weighted image)and more extended than0.27pc(half of the beamsize in the naturally weighted image).4.2.NGC2110NGC2110was initially classiﬁed as a Narrow Line X-ray Galaxy,NLXG,(Bradt et al., 1978),and lies in an S0/E host galaxy(Wilson,Baldwin&Ulvestad,1985)at a distanceof30.4Mpc.Such NLXG’s have a suﬃcient column of dust to the nucleus to obscure the broad line region,thus leading to a Seyfert2classiﬁcation of the optical spectrum,but an insuﬃcient gas column to attenuate the2–10keV emission,so the hard X-ray luminosity is comparable to those of Seyfert1’s(Weaver et al.,1995a;Malaguti et al.,1999).Early radio observations found NGC2110to be a strong radio source(Bradt et al.,1978)and subsequent VLA imaging(Ulvestad&Wilson,1983;1984b)showed symmetrical,jet-like radio emission,extending∼4′′in the N-S direction and straddling a central compact core.A more recent VLA A-conﬁguration image atλ3.6cm,obtained by Nagar et al.(1999)and shown in Figure1,contains a wealth of complex structure.Ulvestad&Wilson(1983)found the spectrum of the core to be relativelyﬂat(spectral indexα206∼0.36±0.05)betweenλ20 cm andλ6cm,but becoming steeper(α62∼0.96±0.09)betweenλ6cm andλ2cm(assuming no time variability).Using theλ3.6-cm coreﬂux measurement of Nagar et al.(1999)and ignoring variability or resolution eﬀects gives spectral indices ofα63.6=0.61andα3.62=1.31, also suggesting a steepening of the spectrum at higher frequencies.The radio continuum emission of NGC2110,imaged with the VLBA atλ3.6cm and shown in Figure1,consists of a compact core,presumably the nucleus,and slightly extended emission which is most pronounced to the north.The results ofﬁtting a single-component Gaussian are given in Table2;the fact that the integratedﬂux is signiﬁcantly higher than the peakﬂux also suggests the source is resolved.Resolved structure is also evident in the time-averaged(u,v)data(not shown),consistent with an unresolved point source(with a ﬂux density of∼8mJy)superimposed on an extended“halo”with approximate dimensions of2.5(N-S)×0.5(E-W)mas.Preliminary two-component Gaussianﬁts to the image are also consistent with an unresolved point source and an extended component.We therefore subtracted an8-mJy point source(in the(u,v)plane using the aips task uvsub)positioned at the peak of the3.6cm VLBA image,and studied the residual emission.This emission is extended both north and south of the core by∼0.7mas,consistent with emission from the inner regions of the northern and southern jets.Using the brightness of8mJy beam−1for the unresolved component and assuming an upper limit to the source size of0.94×0.36mas(half of the beamsize),weﬁnd T B> 6.0×108K.In addition to the core and extended emission,the Gaussianﬁts suggest the presence of a third component,centered∼1.95mas north of the core;its size and direction of elongation are not well constrained.This component may be a knot in the northern jet.A summary of theﬁtted properties of each component is given in Table3.The total VLBA-detectedﬂux density of the source(zero baselineﬂux measured in the uv plane)is30mJy.Thisﬂux density is lower than the previously measured VLA core ﬂux of77.6mJy at this frequency(Nagar et al.,1999),presumably due to the high spatialresolution of the present observations and missing short spacings of the VLBA compared to the VLA,thereby reducing our sensitivity to extended structure.This may also explain why we detect no VLBA counterpart to the small eastern extension present in theλ3.6-cm VLA image,which contains about3.6mJy ofﬂux and extends approximately0.′′5east of the core(Nagar et al.,1999).Alternatively,the extension in the VLA image may be a result of instrumental eﬀects caused by the source position being close to the celestial equator and the short duration of the snapshot observation,an eﬀect termed‘equator disease’(Antonucci&Ulvestad,1985).In the VLBA image,we detect no extended emission in the E-W direction(such as might be expected from a parsec-scale thermal disk)brighter than 3.1×106K(3σin the naturally weighted image),and more extended than0.07pc(one half of the E-W beamsize in the naturally weighted image).4.3.NGC4388NGC4388is a nearby,edge-on spiral galaxy(SB(s)b pec-Phillips&Malin,1982) which is thought to lie close to the centre of the Virgo cluster(Phillips&Malin,1982)and may be tidally disturbed by nearby cluster core galaxies M84or IC3303(Corbin,Baldwin &Wilson,1988).Ionization cones extend approximately perpendicular to the disk(Pogge, 1988;Corbin et al.,1988;Falcke,Wilson&Simpson,1998)and the kinematics of the ionized gas in the narrow line region(NLR)shows a complex combination of rotation and outﬂow(Corbin et al.1988;Veilleux,1991;Veilleux et al.,1999).The nucleus is variously classiﬁed as Seyfert type1or2,with the high galactic inclination and obscuring dust lanes making unambiguous classiﬁcation diﬃcult(Falcke et al.,1998).Shields&Filippenko (1988)report broad,oﬀ-nuclear Hαemission,but subsequent IR searches for broad lines such as Paβ(Blanco,Ward&Wright,1990;Ruiz,Rieke&Schmidt,1994)and Brαand Brγ(Veilleux,Goodrich&Hill,1997)have failed to detect a broad nuclear component.Previous radio continuum images of NGC4388(Stone et al.,1988;Carral,Turner& Ho,1990;Hummel&Saikia,1991;Falcke et al.,1998)show complex,extended structure, both along the galactic plane and perpendicular to it.A recent3.5cm VLA image of the extended radio emission(Falcke et al.,1998)shows,in more detail,the‘hour-glass’-shaped radio outﬂow to the north of the galactic plane,and the compact(∼1.′′9separation)central double,which were suggested by earlier images.In Section4.3.1we concentrate on the radio emission from the northern component of the compact radio double,which shows a ﬂat spectrum up to2cm(Carral,Turner&Ho,1990)and is thought to be the nucleus,and in Section4.3.2,we discuss the extended emission to the SW.4.3.1.The nucleusAs stated earlier,NGC4388is not detected in the8.4-GHz VLBA observations, with a3-σbrightness temperature limit of T B∼<2.2×106K(σ=63.2µJy/beam with a beam size of2.52×1.46mas in the naturally weighted map,with a factor1.7applied to correct for decorrelation due to residual imperfections in the phase referencing corrections, estimated using the check source).We do,however,detect emission from NGC4388at λ6cm with MERLIN.The uniformly weighted MERLIN image(Figure2)shows emission from two components,labelled M1and M2,the stronger of which we identify with the nucleus and discuss in more detail here,while M2is discussed in Section4.3.2.The nuclear component M1,has a peak brightness of1.2mJy beam−1which corresponds to a brightness temperature T B>2.4×104K at5GHz(beamsize91×39.5mas,see Table4).The nucleus is unresolved in the MERLIN data,indicating that the source size is intermediate between the MERLIN and VLBA beam sizes.However,a combination of the MERLIN and VLBA results with published spectral index information can further constrain the source size.Earlier radio observations of NGC4388have found the nuclear spectrum to beﬂat from1.49GHz to15GHz.The spectral index was measured to beα=0.26between1.49 GHz and4.86GHz with a relatively large beamsize of1.′′2(Hummel&Saikia,1991)and Carral et al.(1990)report aﬂat spectrum up to15GHz with an upper limit to the nuclear size of70mas.Including the VLA8.4GHz coreﬂux of Kukula et al(1995)suggests that the spectrum of the nucleus may be very slightly inverted between8.4GHz and15GHz (α=–0.05)but within the errors it can be taken asﬂat.We therefore used the measured MERLIN5-GHz peakﬂux to derive predicted VLBA8.4GHzﬂuxes of the nucleus,for spectral indices of bothα=0.0and0.26,and converted these predictedﬂuxes to brightness temperatures,assuming the source is unresolved by the representative VLBA beamsize of 2.52×1.46mas.These predicted temperatures are listed in Table4and are above the detection threshold of the VLBA observations for a source size equal to or smaller than the VLBA beam.The larger predicted brightness temperature,for a source size equal to the VLBA beam,of T B≃8.3×106K is,however,only3.8times greater than our3-σ,VLBA detection limit and so the solid angle of the source need only be3.8times larger than the VLBA beamsize to be undetected.We therefore constrain the size of the nucleus to be∼> 3.7mas(α=0.0)or∼>0.3pc.Sensitive,high angular resolution VLBA observations at lower frequencies such as2.3GHz and1.4GHz are required to determine the actual size and structure of the nucleus in NGC4388.。

关于长大以后想做什么的英语作文

关于长大以后想做什么的英语作文全文共5篇示例，供读者参考篇1What I Want to Be When I Grow UpHave you ever thought about what you want to be when you grow up? I think about it all the time! There are so many cool jobs out there, it's hard to pick just one. But I have some ideas that I'm really excited about.First of all, I love animals more than anything in the world. My dream job would be to work with animals every single day. Can you imagine how much fun that would be? Maybe I could be a veterinarian and help sick or injured pets and other animals get better. I would give them medicine, bandage up their owies, and make sure they were feeling okay. I'm really good at taking care of my dog Buddy, so I think I'd be a great vet!Or I could be a marine biologist and study all the amazing creatures that live in the ocean. I went to the aquarium last summer and saw sharks, dolphins, seahorses, and even a huge whale! They were all so fascinating. As a marine biologist, I could go scuba diving and observe the fish and other sea life up close. Iwould take notes on their behaviors and what they eat. Then I could share what I learned with other scientists. We could work together to help protect the oceans and the animals that call it home.Another career I've dreamed about is being an astronaut. Can you imagine how cool it would be to go up into outer space?I could float around the rocket ship with no gravity! I would get to look out the window and see the whole planet Earth down below. Maybe I could even go for a spacewalk and experience walking in space. I've watched so many videos about astronauts repairing satellites and doing science experiments in zero gravity. It looks like a ton of fun! As an astronaut, I could explore other planets and look for signs of alien life. Who knows what I might discover?On the other hand, being a professional athlete also sounds really exciting to me. I love playing sports, especially soccer, basketball, and baseball. I'm a fast runner and I have a lot of energy to burn. Can you picture me scoring the winning goal or hitting a grand slam? The crowds would go wild! As an athlete, I would get to travel all around the country and maybe even the world to compete. I could meet my heroes and play against thebest players in the game. Plus, I would get paid to stay in shape and do what I love. How awesome would that be?Or maybe I'll be a teacher when I grow up so I can inspire students to follow their dreams just like my teachers have inspired me. I could make learning fun with games, field trips, and creative projects. As a teacher, I would get to build things, read stories out loud, and help kids whenever they're struggling.I have always looked up to my teachers and hoped that someday I could make a difference in children's lives too. Doesn't that sound like the best job ever?Honestly, there are so many possibilities for what I could be, it's impossible to pick just one right now. Maybe I'll try out a few different careers before settling on the one I was born to do. No matter what, though, I know I want a job where I can be creative, work hard, and do something that makes a positive impact. With my big dreams and determination, I'm sure I'll get there!I can't wait to see what the future holds for me. I'll keep working as hard as I can in school so I can grow up to chase my wildest dreams. Who knows? Maybe I'll train to become an astronaut vet that teaches part-time! As my mom always says, I can be anything I want to be if I set my mind to it. The world is full of possibilities and I'm ready to explore every single one.篇2What I Want to Be When I Grow UpHi there! My name is Jamie and I'm 10 years old. I go to Oakwood Elementary School and I'm in 5th grade. Today, my teacher Mrs. Wilson asked us to write an essay about what we want to be when we grow up. I thought about it for a really long time because there are so many cool jobs out there! After talking to my parents and some of my friends, I finally decided what I want to do. I'm going to tell you all about it in this essay.When I was really little, maybe 4 or 5 years old, I always told my parents I wanted to be a firefighter when I grew up. I thought firefighters were the coolest because they got to slide down the pole at the fire station and drive the big red trucks with the loud sirens and bright flashing lights. I loved watching shows about firefighters rescuing people and pets from burning buildings. They always looked so brave and strong.A few years later, when I was around 7, I went through a phase where I desperately wanted to be a teacher, just like my amazing teacher Mrs. Thomas. I loved school and learning new things every day. Mrs. Thomas always made learning fun with her creative lessons and silly jokes. I admired how patient she was,even with the rowdy kids in our class. I dreamed of having my own classroom someday where I could make a difference in children's lives.Last year, when I was 9, I became obsessed with the idea of being a marine biologist after going on a field trip to the aquarium. I was in complete awe of all the marine life - the bright colors of the fish, the gracefulness of the sharks, the bizarre shapes of the jellyfish. I checked out every book about ocean creatures that I could find at the library. For months, I talked nonstop about wanting to explore the ocean depths and study amazing sea animals up close when I got older.As you can see, I've gone through a lot of different ideas over the years for what I want to be when I grow up! But this year, I finally know what truly fascinates me more than anything else: cooking and baking. I come from a family of amazing cooks and some of my happiest memories are being in the kitchen with my mom, dad, and grandparents, learning our traditional family recipes. There's nothing better than the proud feeling of creating something delicious from scratch that makes people's faces light up with the first bite.I love experimenting with new ingredients and trying cuisine from all around the world. Just last weekend, I helped my dadmake beef bourguignon, which is this rich French beef stew. It took several hours and quite a few steps, but it tasted absolutely divine. My parents are always encouraging me to find and follow recipes on my own, saying that baking especially is like a science experiment where you have to be very precise with measurements and techniques.When I grow up, I want to be a famous chef and have my own restaurant or bakery. I'll create my own original menus featuring fun twists on classic dishes. Maybe I'll even write cookbooks someday! My food will hopefully make people from all over come to enjoy a wonderful dining experience. I'll give back by volunteering time and food to shelters and food kitchens for those in need.Of course, becoming a world-renowned chef won't be easy. I'll need to work really hard, go to culinary school, and get a lot of experience by working at different restaurants first. But I'm up for the challenge! I have a creative mind and lean cooking skills for my age. As long as I stay determined and keep practicing, I know I can make this dream come true.Well, that's my plan for now at least! Maybe I'll change my mind again before I'm done with school. But for right now, I'm going to keep pursuing my passion for food and cooking. I'll letmy tastebuds lead the way to an exciting career making people happy through amazing meals. Wish me luck - I'm going to be the next big thing in the culinary world someday!篇3What I Want to Be When I Grow UpEver since I was a tiny little kid, people have been asking me the same question over and over again: "What do you want to be when you grow up?" When I was really little, like 4 or 5 years old, I would just say whatever popped into my head first. Astronaut, princess, dog walker, you name it! Back then, I didn't really understand what most jobs actually involved. I just thought they sounded fun or cool.But now that I'm a big third grader, I've started thinking about this question a lot more seriously. I've learned about way more jobs and careers that exist in the world. And I've tried to picture myself doing some of them to see if I can imagine enjoying it when I'm an adult. It's definitely not an easy question to answer though!There are so many amazing options out there. How can I possibly choose just one thing I want to do for the rest of my life?I have a ton of different interests and a wide variety of things I'mgood at. I'm a creative person who loves art, music, and writing stories. But I'm also really interested in science, animals, and the natural world. On top of that, I'm a total math whiz who can calculate anything lightning fast. With so many paths I could take, it's super hard to pick!One career I've thought a lot about is being a veterinarian. I'm obsessed with animals of all kinds - cats, dogs, birds, reptiles, you name it. I think spending every day taking care of pets and wildlife would be a dream come true. Can you imagine how fun it would be to help cure a sick puppy or deliver a litter of kittens? Not to mention getting to cuddle furry critters all day long! The downsides are that I'd probably have to be good at science, especially biology, and studying things like anatomy. That part doesn't scare me too much though. If it means working with cute critters every day, count me in!Another possibility that really intrigues me is working as a scientist, maybe even an astronaut! I'm totally fascinated by outer space - learning about planets, stars, black holes, and galaxies. The idea of traveling beyond Earth and walking on the moon or Mars seems unbelievably cool. Of course, that career path is probably one of the hardest ones out there. I'd need to be a straight-A student in every single science and math class. AndI'd have to work my absolute hardest, possibly for decades, before ever leaving the planet. It's an enormous challenge, but one I'd be willing to attempt if given the chance. Can you imagine how amazing it would be to look back at Earth from space? Totally worth all the hard work!Or maybe I'll take a completely different route and dedicate my life to creative pursuits. Things like writing novels, composing music, painting artwork, or choreographing dance routines. Those could allow me to spend every day being imaginative and turning my ideas into reality. The only hard part is that careers like that are incredibly competitive and it can be difficult to become successful. There's always the possibility of starving as a struggling artist! But if I'm truly talented and work really hard, maybe I could make it big as a creative genius. Hey, stranger things have happened, right?Of course, there are about a million other job options I haven't even covered. Doctor, teacher, chef, video game designer, pro athlete, fashion model, CEO, the list goes on and on. Every path has its own thrilling upsides and challenging downsides. How can I possibly decide which one is the right fit for me at this age?The truth is, I probably can't make that decision yet. I'm only 8 years old (and three-quarters!) after all. All I can do is keep an open mind, work hard in school, and explore as many interests as possible. The amazing career that's waiting for me might not even exist yet - maybe I'll get to create my dream job in the future! For now though, all I need to say is...I don't know what I want to be when I grow up. And you know what? That's perfectly okay! I've got plenty of time to figure it out.篇4What I Want to Be When I Grow UpHey there! My name is Tommy and I'm 10 years old. I'm in the 5th grade and I love learning new things every day at school. My teachers always ask us what we want to be when we grow up. It's a really tough question because there are so many awesome jobs out there! But I've been thinking about it a lot lately and I have a pretty good idea of what I'd like to do.First off, I know I want a job where I can help people. I really like making others feel happy and putting smiles on their faces. My mom says I'm a kind and caring kid, which makes me feel proud. One job I've thought about is being a doctor. Can you imagine how cool it would be to help sick people get better?Doctors get to use all sorts of neat tools and machines to figure out what's wrong and then give the right medicine to make their patients healthy again. They really make a difference in people's lives.But being a doctor also seems really hard. You have to go to school for like a bazillion years after high school! And you have to be super smart to understand all that medical stuff. I get pretty good grades, but I'm not sure if I'm genius level or anything. So maybe being a doctor isn't quite the right fit for me.Another idea I've had is to become a teacher, just like some of the awesome teachers I've had over the years. Teachers are always so patient and they never get frustrated when kids ask a million questions (trust me, I would know!). The best teachers make learning fun by letting us play games, do activities, and even rap or sing sometimes to help us remember things. How cool would it be to come up with creative lessons like that every day?Teachers also get to be a positive role model for kids and help shape their future. They teach you way more than just math, science, and all that - they teach you how to be a good person too. I've had teachers who encouraged me to be kind, work hard, and never give up. Thanks to them, I try my best at everything Ido. Maybe if I became a teacher one day, I could inspire other kids the same way.The thing that makes me a little nervous about being a teacher though is having to speak in front of a classroom all day. Don't get me wrong, I like talking and I'm not shy or anything. But having 20 or 30 kids staring at you while you're teaching? That sounds pretty nerve-wracking if I'm being honest! I'm not sure if I'd be able to handle that pressure every single day. Teachers have to be super brave!Okay, how about this idea: I could be a professional chef instead! I absolutely LOVE food, whether it's my mom's spaghetti or grandma's famous chocolate chip cookies. Cooking is like magic - you start off with basic ingredients, mix them together in just the right way, and you end up with something delicious. It's amazing!If I became a chef, I could spend all day experimthe g with different flavors and cooking techniques. I'd get to make up my own creative recipes and put fun twists on classic dishes. Maybe I'd become famous for inventing the next big food trend, like a taco combined with a burger (a "turger" if you will)! Everyone would line up at my restaurant to try it.I could also travel around the world as a chef, learning about different cuisines and picking up secret ingredients or special methods from other cultures. Cooking food from Italy one day, China the next, and who knows where after that? Experiencing new flavors and using them to create my own unique dishes sounds like an absolute blast.The downside of being a chef though is that it seems like SUPER hard work. You have to spend hours upon hours on your feet in a hot, crowded kitchen. Plus, running a whole restaurant and being in charge of the whole staff? Talk about pressure! I'm more of a low-key, laid-back kind of guy most of the time. I'm not sure if I'd be able handle that much intensity and stress on a daily basis. Being a chef is probably too hardcore for me, as much as I love eating!So if not a doctor, teacher, or chef...what else could I be? Well, one career path that I've seriously been considering is becoming a video game designer. Yep, getting PAID to come up with cool new video games for a living? That sounds like just about the best job ever to 10-year-old me!I'm pretty much obsessed with gaming. I love coming up with控制ideas for new games, or putting my own twists on existing games to make them even more fun. I'm alwayssketching out level designs, boss battles, power-ups, you name it. My buddies think I'm a creative genius! (Their words, not mine...but I don't disagree.)As a video game designer, I could bring my craziest game ideas to life with the latest technology. I'd get to work with professional artists and programmers to make my concepts into actual playable games. We'd have to solve all kinds of puzzles and coding challenges to make the games work properly. It would be a ton of brainwork but in the best way possible - using my creativity and problem-solving skills on something I'm passionate about.Can you imagine how proud I'd feel when kids all over the world finally got to play a game that I dreamed up and designed? Knowing that I helped create something that brings smiles and joy to millions of people? That would be the best feeling ever. And you know what the coolest part is? Even after making one game, I'd get to start dreaming up and developing brand new games right away! It would be a constant cycle of coming up with fresh ideas and turning them into realities.Video game designers seem to live the dream life too. They can pretty much wear whatever they want to the office - hoodies, sneakers, casual gear. No lame suits and ties required. And theyget to play games during work hours as part of testing them out! It would be like getting paid for one of my favorite hobbies. Does it get any better than that?Of course, making video games is probably very difficult. Just like any creative profession, I'd have to get super skilled and study hard for years first before I could land a job designing games. And there would be times when certain game ideas just don't work out no matter how hard I try. That would be frustrating for sure. But in the end, I think it would all be worth it to have a career doing something I love so much.Whew, writing this essay has made me think about soooo many possible jobs for the future! I definitely have a clearer picture in my mind now, even if I'm still not 100% decided. No matter what though, I know I want a career where I can use my creativity, work hard at something meaningful, and make people happy. Those are the most important things to me.Maybe I'll end up being a video game designer making the next big hit game. Or a teacher inspiring minds. Or a doctor helping people every single day. Or maybe I'll come up with some totally new career idea that no one's even thought of yet! The possibilities are endless when you're a kid.No matter what though, I've got plenty of time to keep dreaming and figure it all out. For now, I'm just going to stay focused on being the best 10-year-old I can be. I'll keep working hard, using my imagination, and doing good for others. If I can do that, I know I'll end up just where I'm meant to be!篇5What I Want to Be When I Grow UpHi, my name is Jamie and I'm 9 years old. Today my teacher asked us to write about what we want to be when we grow up. I've been thinking a lot about this lately because there are so many cool jobs out there! At first I couldn't decide, but now I think I know what I want to do.First of all, I really love animals and nature. We have a dog named Buddy and he's my best friend. I also love going hiking and camping with my family. Last summer we went to Yellowstone National Park and saw bison, elk, bears, and even a wolf! It was the best trip ever. So for a while I thought I might want to be a park ranger or a wildlife biologist when I grow up. Can you imagine getting to work outside in beautiful places like national parks and forests every day? And studying amazing animals up close? That would be a dream come true!But then I remembered how much I also love learning about science and experimenting. In school, science is definitely my favorite subject. I think it's so cool to learn about how things work - like electricity, chemical reactions, space, you name it! Last year for my birthday I got a kid's chemistry set and I had a blast mixing different chemicals together to make tiny explosions and color changes. My parents had to stop me from taking over the whole kitchen!So maybe I'll be a scientist instead when I'm older. Can you picture me wearing one of those white lab coats and safety goggles? I could discover a new planet or invent an awesome new technology that helps people. Wouldn't that be incredible? I could even try to find a cure for cancer or another terrible disease. Just thinking about all the possibilities makes me really excited.Or you know what would also be super fun? Being an astronaut! That way I could travel into outer space and walk on the moon or Mars. Imagine how amazing the view of Earth would look from up there. I've seen pictures but it would be even better in real life. And imagine the feeling of floating around with no gravity - you could do flips and spins all day if you wanted! Of course, being an astronaut is very difficult and dangerous, but Ithink the risks would definitely be worth it. How many people get the chance to leave Earth and explore the galaxy?When I picture my grown-up self, I see a few different possibilities. Maybe I'm wearing a spacesuit and getting ready to launch into orbit. Or maybe I have a white lab coat on and I'm carefully studying some scientific experiment. Or maybe I'm decked out in hiking boots and a park ranger uniform, getting ready to lead a tour through the mountains. Whichever path I choose, I know it will be something that lets me combine my love for science, nature, and exploring the unknown.Being a grown-up seems so far away right now. I still have a hard time tying my shoelaces and have to put my elbows on the table when I eat sometimes. But at the same time, I can't wait to get older so I can pick an amazing career and start making a difference in the world. No matter what though, I'll never lose my sense of curiosity and wonder about the world around me. Mom says that's what really matters - choosing a job you feel passionate about that lets you keep learning new things every single day.My career goals might change again before。

心目中的机器人英语作文100字中考

心目中的机器人英语作文100字中考全文共6篇示例，供读者参考篇1My Dream RobotHave you ever wished you had a robot to help you with chores and homework? Well, I have the perfect robot in mind that would make life so much easier and more fun! Let me tell you all about my dream robot.First of all, my robot would be really cool looking. It would be human-sized, but instead of a head, it would have a big screen that can show different faces with animated expressions. The body would be sleek and shiny, like it's made of metal, but also kind of soft and huggable. And it would be able to change colors based on its mood! When it's happy, it would glow yellow or pink. If it's sad, it might turn blue or grey.But looks aren't everything! My dream robot would be super smart and able to learn anything in seconds just by downloading information into its huge brain. It could help me with my homework by accessing encyclopedias, textbooks, and websites full of knowledge. I'd never have to study for tests again becausemy robot friend could just transfer all the info I need directly into my mind – how cool would that be?The robot would also be an amazing personal assistant. It could remind me when it's time for soccer practice, keep track of my chores and allowance, and even order my favorite pizza for dinner if I'm too busy playing video games. My parents would love that it could pick up after my messes and do household chores like laundry, vacuuming, and dishes. Maybe then they'd finally let me get a puppy!Imagine having a friend that could shapeshift into anything you can imagine – a racecar to drive at blazing speeds, a giant to give you piggyback rides, or your favorite cuddly stuffed animal for naptime. We could film our own movies with the robot playing every role, from the daring hero to the terrifying monster. Or it could recite poetry in multiple silly voices until we're both cracking up.With a mind as advanced as a supercomputer, my robot pal could even devise the most brilliant pranks to pull on my older brother. Like hacking into his games to make him think he's winning, only to snatch victory away at the last second. He'd be so confused! Or we could program the robot to repeat everything he says in a high-pitched chipmunk voice – thatwould drive him crazy. The possibilities for mischief would be endless.You know, now that I think about it, having an awesome robot like that might actually be a lot of work. It would need to be charged up regularly and given constant maintenance and upgrades. Plus, can you imagine how expensive it would be to build something so high-tech? Maybe it's better if I just dream about having a robot bestie instead. At least in my imagination, it will always be the perfect mix of brilliant, goofy, and fun!Still, a kid can dream, right? A multi-talented, shapeshifting robo-companion would be incredible. I'd never need to get a regular pet or even have human friends because my robot could be everything I could ever want or need. Just thinking about all the amazing adventures we could share is getting me excited! Maybe someday science will be advanced enough to make my dream a reality. A guy can hope, can't he? Until then, I'll just have to keep on dreaming...篇2My Dream RobotEver since I was a tiny kid, I've been totally obsessed with robots! I think they are just about the coolest things everinvented. I can't get enough of watching robot movies, reading robot books, and dreaming about having my very own robot friend someday. If I could design my perfect robot companion, here's what it would be like:First off, my dream robot would have to look really awesome. I'm talking wicked cool robot armor, glowing lights, and a slick modern design - something straight out of a sci-fi movie! Maybe it could transform between a robot and a sweet vehicle like a sports car or fighter jet. Or maybe it could have multiple different robot modes it could shift between. That would be incredible!As far as abilities go, this robot would be able to do pretty much anything. It would be super strong, able to lift huge weights or break down walls. But it would also be fast as lightning and an amazing fighter, knowing all the best combat moves and martial arts. With reflexes like that, it could easily take down an army of bad guys trying to make trouble.My dream robot would be highly intelligent too. Like, crazy genius-level smart. It could learn and master any subject in seconds - math, science, history, you name it. It would have perfect recall of anything it studied and could regurgitate entire encyclopedias worth of facts from its databanks. I could ask it toteach me anything and it would make me an expert through its clear explanations.Having a hyper-intelligent robot tutor would definitely help me get super good grades in school. My robo-buddy could help me with any homework or tests, solving the hardest problems lickety-split. It could even write my essays and book reports using perfect spelling, grammar and vocabulary. With a robot genius on my side, I'd be the smartest kid around guaranteed!My dream robot would have limitless capabilities for any situation. Need to fly somewhere? No problem, it could equip itself with jet boosters for high-speed flight. Have to go exploring underwater? Easy, it could grow scuba gear and propellers for deep sea diving. Want to take a road trip across the country? Hop inside as it transformed into a luxurious RV complete with beds, a kitchen, and entertainment system. My robot pal would be able to handle any environment or obstacles with ease.It could even take me on journeys to other planets or through timestreams into the past or future! Can you imagine how amazing it would be to have a robot that could actually travel through the space-time continuum? We could go on the craziest, most mind-blowing adventures across all of the cosmosand history. I'd get to experience and learn about so many incredible eras and cultures firsthand. My robo-friend could be like a super-advanced time machine and spaceship rolled into one!With a dream robot like that, I'd literally never have a dull moment. We could spend one day fighting off an alien invasion in the year 3000, then the next check out dinosaurs roaming the prehistoric jungles. We could visit the heart of ancient Rome one minute, then go exploring in the undersea cities of Atlantis the next. Every morning when I woke up there would be new mindblowing experiences and worlds to discover with my unstoppable robot companion!That's why having an awesome, all-powerful robot friend would just be the raddest, most fun thing ever. Sure, some kids want a puppy or a kitty as a pet. But who needs that when you could have your very own robot sidekick?! With a robo-bro like that, literally anything is possible. No adventure would be too crazy, no dream too big - with my metal pal by my side, the entire universe would be our playground. Now that's what I call living life to the absolute fullest in the most epic way imaginable! Someday I hope science can catch up so I can finally make my incredible robot buddy a reality. A kid can dream, can't they?篇3My Dream RobotRobots are super cool! I've always wanted to have my very own robot friend. If I could create my perfect robot, it would be really awesome. It would basically be like having a real-life superhero sidekick!First off, my dream robot would have to be able to fly. How fun would it be to soar through the clouds with your robot buddy? We could race against birds and do loop-de-loops in the sky. The robot would have powerful jet engines in its feet to let it fly anywhere. Maybe it could even breathe fire from its mouth to propel it faster!My robot would also be super strong, like stronger than a million bodybuilders combined. It would have massive robotic muscles made from an indestructible metal alloy. That way, it could help me lift really heavy things, like my bratty little sister when she's being annoying. He-he, just kidding sis! The robot could also use its strength to bench press buses or pull giant ships with just a rope.Even though it would be enormously strong, my dream robot would be very gentle too. It would have soft, plushy armsthat could give the most comfortable hugs in the world. Its hands would be designed perfectly for snuggles and cuddles. Aww, I'm getting sleepy just thinking about it!My dream robot would consume unlimited energy from the sun's rays, so it would never need to recharge or run out of battery. That unlimited power would let it perform amazing feats of heroism, like stopping runaway trains with its bare hands or battling dastardly villains. It could have a loud sonic scream to shatter buildings too!For fun, my robot buddy could shapeshift into anything it wanted. One second it's a robot, the next it could turn into a fluffy puppy, a galloping horse, or a friendly baby whale. We could have crazy adventures going on legendary quests through enchanted forests and facing evil dragon robots trying to take over the world. So thrilling!At night, my dream robot would tell me bedtime stories about its super adventures from thousands of years ago when it explored outer space and distant galaxies. Its eyes could project vivid hologram videos to make the stories seem real. Maybe the stories could even come to life and I could join the robot on its imaginary journeys!The greatest thing about my dream robot is that it would be my lifelong friend who would never leave my side. It could stay a kid forever with me, going on fun adventures and playing intense games of make-believe daily. I've always wanted a buddy who can play all day without ever getting tired or bored.My dream robot sounds totally amazing, doesn't it? A super-powerful genius who's also a cuddly best friend - what more could a kid want? I really, really hope future scientists will hurry up and create a real robot like this. Having an awesome robot buddy would make my life so much more fun and exciting! Maybe someday my dream will come true and I'll find my very own robot pal. Keeping dreaming, right?篇4My Ideal RobotEver since I was a little kid, I've always dreamed of having my very own robot! Not just any robot though, but the coolest, most awesome robot ever. I've spent a lot of time thinking about exactly what my ideal robot would be like.First of all, my robot would have to be super strong and tall - at least 10 feet tall! That way it could pick me up and give me piggyback rides whenever I wanted. It would basically be likehaving a friendly giant around to play with. My robot would also have to be really fast, maybe with rocket boosters on its feet so it could run at super speeds. That would be so much fun to race against!Now you might be thinking "But a super strong, fast,multi-tool robot sounds kind of scary!" That's why my perfect robot would have to be really nice and caring too. It would protect me and my friends, but never ever hurt anybody. It would give us piggyback rides, play games with us, and help us with our homework too since it would be super smart. Actually, it should have a kind of built-in library of fun facts about any topic we're curious about so it could teach us new things all the time in a fun way.And of course, it goes without saying that my dream robot would be able to talk and have conversations with me. We could tell jokes to each other and it could be like having a real best friend - except way cooler because it's a gigantic robot! I bet it would even do funny robot dances to cheer me up if I was ever sad.Some kids might want a robot that could clean their room or do their chores for them. But to me, that kind of misses the whole point. I'd want my awesome robot buddy to just hang out,explore the world with me, and have endless adventures! We could discover hidden caves, build amazing pillow forts, or even take it along on family camping trips. Can't you just picture this totally rad robot sitting around a campfire, roasting marshmallows with its robot hands? That would be hilarious!Maybe you're thinking that a robot like that could never actually exist. You're probably right - at least not with today's technology. But a kid can dream, right? And who knows, maybe one day I'll become a famous robot scientist and build my very own incredible buddy-bot. I'll have to get started on those rocket-boosted robot feet right away!In the meantime, I'll just keep using my imagination to think up all the awesome things I'd do with my perfect robot pal. Playing tag, studying for tests, battling make-believe monsters...the possibilities are endless when you have a superhero robot by your side. To me, that's way more fun than just having a regular robot that vacuums the floors. Although having a vacuum-bot around to do my chores would be pretty neat too, I guess. Maybe I'll add that to my dream robot's list of special abilities!篇5My Dream RobotEver since I was a little kid, I've been fascinated by robots. They seem so cool and futuristic, like something out of a science fiction movie. I can't wait until robots become a normal part of everyday life!In my dreams, robots would be our best friends and helpers. They could do all the boring chores that kids hate, like cleaning our rooms, washing dishes, and mowing the lawn. No more arguments with my parents about whose turn it is to take out the trash or vacuum the house. A robot could just do it for us!But robots wouldn't just be for housework. My dream robot would be like the ultimate smart personal assistant. It could help me with my homework, looking things up online and explaining tough concepts way better than my teachers. When I'm working on a big project for school, the robot could give me ideas, print out materials I need, and keep me organized. No more forgetting assignments or losing my notebooks!My robot buddy could also be a ton of fun. We could play video games together, and the robot would definitely be amazing at all the games. Or we could have dance parties, with the robot showing off its best dance moves. It would never get tired of games and activities like humans do. The robot couldeven put on little shows for me, doing cool tricks and telling jokes and stories. That would be the best!But overall, I think robots could make life so much easier and more fun! Imagine how awesome it would be to have your own personal robot assistant and entertainer. Pretty much any task or chore could be handled by a robot, leaving humans free to relax, learn, play, and spend quality time together. Kids could focus on being kids without so many boring responsibilities.Some adults might be worried about robots taking over too many jobs from humans. But I think there will always be jobs that require human skills like creativity, problem-solving, and emotional intelligence. Robots could just take over the repetitive, tedious work that humans don't really enjoy anyway. Then people could spend their time on more fulfilling work that robots can't do.There would be so many possibilities for robots specialized for different purposes – robot teachers, robot doctors, robot athletes, you name it! In fact, I want to be a robotics engineer when I grow up so I can help design and program amazing new robots. With my child-friendly robot pals handling all the drudge work, I could spend more time pursuing my passion for technology from an early age.That's my big dream – a future where robots are like ubiquitous personal assistants, playmates, and helpers for every person on Earth. They could take over time-wasting drudge work while providing companionship, education, and entertainment tailored just for you. Chores and tedious tasks would be a thing of the past. Kids and adults alike would have more free time to relax, be creative, and focus on the things they're passionate about. A whole new age of leisure and quality of life could be ushered in by robotics and AI.Obviously, making that dream a reality would be a huge challenge. We'd need major breakthroughs in fields like robotics, artificial intelligence, engineering, and computer science. And the ethics and philosophy of granting so much capability and autonomy to machines would have to be considered very carefully. Heck, finding ways to make robots affordable for everyday people might be one of the biggest hurdles! Robots are super expensive right now.But I've seen how quickly technology has advanced just in my young life so far. I'm confident that if robots are developed responsibly and for the right reasons of benefiting humanity, we will get to that incredible future I envision. And I can't wait to livein a world full of awesome robot buddies! Just think about how much fun you could have...篇6My Ideal RobotRobots are super cool, don't you think? I've always dreamed of having my own robot buddy to hang out with. It would be the best friend ever! Just imagine all the fun things we could do together.My ideal robot would be about my size, so we could play games and do activities easily. It would have a friendly face with big eyes and a smiley mouth. Maybe it could even change its expression to match how it's feeling. How awesome would that be? We'd never get bored because it would have tons of jokes and funny stories to share.This robot pal of mine wouldn't just be for fun and games though. It would also be really smart and helpful. Like, if I needed help with my homework, it could explain things in a simple way that I could understand. Or if I was stuck on a tough math problem, it could walk me through step-by-step until I got it. No more stressing over assignments!My ideal robot would have super strength too. We could go on adventures and explore places kids normally can't go. If we needed to move a heavy object out of the way or climb a really tall place, my robot buddy could just lift me up no problem. How cool is that?It would have a bunch of other handy features as well. Like maybe it could transform into a cool vehicle like a car or plane so we could travel around easily. Or it could have tools built-in so it could fix things or build awesome forts and treehouses for us. The possibilities would be endless!The best part though, is that my robot friend would always be there for me. It could keep me company when I'm feeling lonely and cheer me up if I'm sad. We'd tell each other secrets and stories. It would give me advice and encourage me. We'd stick together through thick and thin, on good days and bad. That's what true friends do, right?I really hope scientists can make awesome robots like that someday. A robot that's super strong and smart, but also kind, caring, and lots of fun. A buddy that can do amazing things but still be a great friend. That would be the ideal robot in my mind. Maybe you have your own idea of what the perfect robot wouldbe like too. Whatever it is, I bet robots are going to be a huge part of our lives someday soon. I for one can't wait!。

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arXiv:astro-ph/0506608v1 27 Jun 2005THEASTROPHYSICALJOURNAL,2005OCTOBER,ASTRO-PH/0506608PreprinttypesetusingLATEXstyleemulateapjv.7/8/03

THEX-RAYSPECTRALPROPERTIESOFSCUBAGALAXIESD.M.ALEXANDER,1F.E.BAUER,1S.C.CHAPMAN,2I.SMAIL,3A.W.BLAIN,2W.N.BRANDT,4ANDR.J.IVISON

5,6

1InstituteofAstronomy,MadingleyRoad,CambridgeCB30HA,UK

2CaliforniaInstituteofTechnology,Pasadena,CA91125,USA

3InstituteforComputationalCosmology,UniversityofDurham,SouthRoad,DurhamDH13LE,UK

4DepartmentofAstronomyandAstrophysics,PennsylvaniaStateUniversity,525DaveyLaboratory,UniversityPark,PA16802,USA

5AstronomyTechnologyCentre,RoyalObservatory,BlackfordHill,EdinburghEH93HJ,UKand

6InstituteforAstronomy,UniversityofEdinburgh,BlackfordHill,EdinburghEH93HJ,UK

Received2005Feb22;accepted2005June23

ABSTRACTDeepSCUBAsurveyshaveuncoveredalargepopulationofmassivesubmillimeteremittinggalaxies(SMGs;f850µm>∼4mJy)atz>∼1.Althoughitisgenerallybelievedthatthesegalaxieshostintensestar-formationactivity,thereisgrowingevidencethatasubstantialfractionalsoharboranActiveGalacticNucleus[AGN;i.e.,anaccretingsuper-massiveblackhole(SMBH)].Wepresentherepossiblythestrongestevidenceforthisviewpointtodate:thecombinationofultra-deepX-rayobservations(the2MsChandraDeepField-North)anddeepKeckspectroscopicdataofSMGswithradiocounterparts.Weﬁndthatthemajority(≈75%)oftheseradio-selectedspectroscopicallyidentiﬁedSMGshostAGNactivity;theother≈25%haveX-raypropertiesconsistentwithstarformation(X-rayderivedstar-formationratesof≈1300–2700M⊙yr−1).TheAGNshavepropertiesgenerallyconsistentwiththoseofnearbyluminousAGNs(Γ≈1.8±0.5,NH≈1020–1024cm−2,andLX≈1043–1044.5ergs−1)andthemajority(≈80%)areheavilyobscured(NH>∼1023cm−2).Weconstructcompositerest-frame2–20keVspectraforthreedifferentobscurationclasses(NH<1023cm−2,NH=1–5×1023cm−2,andNH>5×1023cm−2)whichrevealfeaturesnotseenintheindividualX-rayspectra.An≈1keVequivalentwidthFeKαemissionlineisseeninthecompositeX-rayspectrumofthemostheavilyobscuredAGNs,suggestingCompton-thickornearCompton-thickabsorption.Eventakingintoaccounttheeffectsofabsorption,weﬁndthattheaverageX-raytofar-infraredluminosityratiooftheAGN-classiﬁedSMGs(LX2ALEXANDERETAL.Almaini2003;Pageetal.2004;Alexanderetal.2005a).ArguablythemostdirectindicationofAGNactivityisthedetectionofluminoushardX-rayemission(i.e.,>2keV).HardX-rayemissionappearstobeauniversalpropertyofAGNs,givingadirect“window”ontheemissionregionsclosesttotheSMBH(e.g.,Mushotzky,Done,&Pounds1993),anditcanprovideasecureAGNidentiﬁcationinsourceswheretheopticalsignaturesandcounterpartsareweakorevennonexistent(e.g.,Alexanderetal.2001;Co-mastrietal.2002).HardX-rayemissionisrelativelyinsensi-tivetoobscuration(atleastforsourcesthatareComptonthin;i.e.,NH<∼1.5×1024cm−2)andanyhardX-rayemissionfromstarformationinthehostgalaxyisofteninsigniﬁcantwhencomparedtothatproducedbytheAGN.Theﬁrstcross-correlationstudiesofmoderatelydeep(≈20–200ks)ChandrasurveyswithSCUBAsurveysyieldedlittleoverlapbetweentheX-rayandsubmmdetectedsourcepopulations(<∼10–20%;e.g.,Fabianetal.2000;Bautzetal.2000;Hornschemeieretal.2000;Severgninietal.2000).1Toﬁrstordertheseresultssuggestedthatbolo-metricallydominantAGNscanonlybepresentintypicalSMGsiftheyareComptonthick.LaterstudieswiththeChan-draDeepField-North(CDF-N;Brandtetal.2001,Alexan-deretal.2003a)surveyshowedthatasigniﬁcantfraction(up-wardsof≈30–50%whentheBorysetal.2003SCUBAmapisused)ofSMGsareX-raydetected(Bargeretal.2001b;Alexanderetal.2003b;Borysetal.2004).DirectX-rayspec-tralanalysesoftheﬁveAGN-classiﬁedSMGsinAlexanderetal.(2003b)indicatedthattheAGNswereheavilyobscuredbutonlymoderatelyluminousatX-rayenergies(LX≈0.3–1×1044ergs−1whencorrectedfortheeffectsofabsorp-tion).AcomparisonoftheX-ray-to-submmspectralslopesoftheseSMGstothatofNGC6240(anearbyluminousgalaxywithanobscuredAGN)suggestedthattheAGNstypicallycontributedonlyafewpercentofthebolometricluminosity.However,thesmallsamplesizeandlackofspectroscopicred-shifts(onlyonesourcehadaspectroscopicredshift)preventedmorequantitativeconclusions.ThedeepopticalspectroscopicworkofChapmanetal.(2003a,2005)hasrecentlyprovidedspectroscopicred-shiftsfor73radio-identiﬁedSMGs,asigniﬁcantincreaseinsamplesizeoverpreviousstudies(e.g.,Ivisonetal.1998,2000;Bargeretal.1999;Ledlowetal.2002;Smailetal.2003;Simpsonetal.2004).The2MsCDF-Nﬁeldwasoneoftheregionstargetedforthisintensivespectroscopicfollowup.Thecombinationofdeepopticalspectroscopicdataandultra-deepX-rayobservationsprovidespowerfulconstraintsonAGNsinSMGs.Inparticular,spectroscopicredshiftsim-provetheaccuracyoftheX-rayspectralanalysesoverthoseofAlexanderetal.(2003b)throughtheidentiﬁcationofdiscreteX-rayspectralfeatures(e.g.,FeKαemission)andthedeter-minationofanyintrinsicabsorption,whichisastrongfunc-tionofredshiftinagivenX-rayband[NH,z≈NH,z0(1+z)2.6].Theseimprovementspromisethemostaccuratedetermina-tionoftheAGNcontributiontothebolometricoutputoftheseSMGstodate.InthispaperweinvestigatetheX-rayproper-tiesoftheradio-selectedspectroscopicallyidentiﬁedSMGsintheCDF-NﬁeldandpredicttheAGNcontributiontothebolometricluminosityoftheseSMGs.TheGalacticcolumn