托福听力资料托福tpo15听力文本 (2)
历年托福听力真题
历年托福听力真题历年托福听力真题精选Conversation 1女生想加入爵士乐队，尽管专业是其他但音乐是爱好，想继续保持。
但教授的team已经不缺人了，教授建议她自己多关于Website，学生band会更新信息。
-TPO部分对应参考(社团生活TPO11-C1/TPO15-C1/TPO26-C1) -TPO对应词汇校内工作，课外活动及寻找经济援助：Letterof reference/recommendationCompetitiveBenefitfuture careerFieldresearchCollectdata for papersWaiter,waitress，BabysitterWorkat the libraryQualification资格,qualified 合格的Resume,CVfinancialaid经济援助ScholarshipFellowshipTeachingassistantship 助教奖学金Researchassistantship 研究奖学金Grant助学金Loan 贷款Need-based以需求为基础Merit-based以优秀为基础Studentunion 学生会Clubs俱乐部Membership成员资格CareerserviceLecture 1自然科学类。
讲矮行星是如何形成的，与行星的区别。
一个是ejection theory，跟gravity的原因有关。
第二个就是吸收的material 无法发光，屏幕给了这两个theory的名词提醒。
-TPO部分对应参考(天文学TPO18-L1/TPO24-L4/T13-L4)-参考背景Sufficient internal pressure, caused by the body's gravitation, will turn abody plastic, andsufficient plasticity will allow high elevations to sink and hollows to fillin, a process known as gravitational relaxation. Bodies smaller than a fewkilometers are dominated by non-gravitational forces and tend to have anirregular shape. The Saturnian moon Methone, at around 3 km in diameter, is a roundedbut tidally elongated egg-shape. Larger objects, where gravitation issignificant but not dominant, are "potato" shaped; the more massivethe body is, the higher its internal pressure and the more rounded its shape,until the pressure is sufficient to overcome its internal compressive strength and it achieves hydrostatic equilibrium. At this point a body is as round as it is possible to be, given itsrotation and tidal effects, and is an ellipsoid in shape. This is the defining limit of a dwarf planet.When an object is in hydrostatic equilibrium, a global layer of liquidcovering its surface would form a liquid surface of the same shape as the body,apart from small-scale surface features such as craters and fissures. If thebody does not rotate, it will be a sphere, but the faster it does rotate, themore oblate or even scalene it becomes. However, if such a rotating body were to be heated until itmelted, its overall shape would not change whenliquid. The extreme example ofa non-spherical body in hydrostatic equilibrium is Haumea, whichis twice as long along its major axis as it is at the poles. If the body has amassive nearby companion, then tidal forces come into effect as well,distorting it into a prolate spheroid. An example of this is Jupiter's moon Io, which is the most volcanically active bodyin the Solar System due to effects of tidal heating. Tidal forces also cause a body's rotationto gradually become tidally locked, such that it always presents the same faceto its companion. An extreme example of this is the Pluto–Charon system, whereboth bodies are tidally locked to each other. Earth's Moon is also tidally locked, as are many satellites of the gas giants.Lecture 2社会科学类。
剑桥15-test3 -part 2 原文
Cambridge IELTS 15 Test 3 Audio scriptPART 2 (Q11-16)PRESENTER: My guest on the show today is Alice Riches who started the Street Play Scheme where she lives in Beechwood Road. For those of you that don’t already know - Street Play involves local residents closing off their street for a few hours so that children have chance to play in the street safely. She started it in her own street, Beechwood Road, and the idea caught on, and there are now Street Play Scheme all over the city. So when did you actually start the scheme, Alice?ALICE: Well, I first had the idea when my oldest child was still a toddler, so that’s about six years ago now – but it tool at least two years of campaigning before we were actually able to make it happen. So the scheme’s been up and running for three years now. [Q11] We’d love to be able to close our road for longer –for the whole weekend, from Saturday morning until Sunday evening, for example. At the moment it’s just once a week. But when we started it was only a month. [Q12] But we’re working on it.PRESENTER: So what actually happens when Beechwood Road is closed?ALICE: We have volunteer wardens, mostly parents but some elderly residents too, who block off our road at either end. The council have provided special signs but there’s always a volunteer there to explain what’s happening to a ny motorists. [Q13] Generally, they’re fine about it –we’ve only had to get the police involved once or twice.Now I should explain that the road isn’t completely closed to cars. But only residents’ cars are allowed. If people really need to get in or ou r of Beechwood Road, it’s not a problem – as long as they drive at under 20 kilometres per hour. [Q14] But most people just decide not to use their cars during this time, or they park in another street. The wardens are only there to stop through traffic.PRESENTER: So can anyone apply to get involved in Street Play?ALICE: Absolutely – we want to include all kids in the city –especially those who live on busy roads. It’s here that demand is greatest. [Q15] Obviously, there isn’t such demand in wealthierareas where the children have access to parks or large gardens –or in the suburbs where there are usually more places for children to play outside.I’d recommend that anyone listening who likes the idea should just give it a go. We’ve been surprised by th e positive reaction of residents all over the city. And that’s not just parents. There are always a few who complain but they’ve very happy to see children out on the street – even if it does get quite noisy. [Q16]PART 2 (Q17-20)ALICE: There have been so many benefits of Street Play for the kids. Parents really like the fact that the kids are getting fresh air instead of sitting staring at a computer screen, even of they’re not doing anything particularly energetic. And of course it’s great that kids can play with their friends outside without being supervised by their parents – but for me the biggest advantage is that kids develop confidence themselves to be outside without their parents. [Q17] The other really fantastic thing is that children get to know the adults in the street –it’s like having a big extended family. [Q18]PRESENTER: It certainly does have a lot of benefits. I want to move on now and ask you about a related project in King Street.ALICE: Right. Well this was an experiment I was involved in where local residents decided to try and reduce the traffic along King Street, which is the busiest main road in our area, by persuading people not to use their cars for one day. We thought about making people pay more for parking – but we decided that would be really unpopular – so instead we just stopped people from parking on King Street but left the other car parks open.It was surprising how much of a difference all this made. As we’d predicted, air quality was significantly better but what I had n’t expected was how much quieter it would be – even with the buses still running. [Q19] Of course everyone said they felt safer but we were actually amazed that sales in the shops went up considerably that day –we thought there’d be fewer people out shopping – not more. [Q20]PRESENTER: Good morning. That’s really interesting so the fact that…。
托福TPO15听力Conversation2文本+题目+答案解析
为了帮助大家高效备考托福，为大家带来托福TPO15听力Conversation2文本+题目+答案解析，希望对大家备考有所帮助。
托福TPO15听力Conversation2文本 Narrator: Listen to part of a conversation between a student and her biology professor. Professor: Hi, Samantha, how did your track meet go? Student: Great! I placed first in one race and third in another. Professor: Congratulations, you must practice a lot. Student: Three times a week pre-season, but now that we are competing every weekend. We practice six days a week from 3:30 to 5. Professor: Athletics places a heavy demand on your time, don’t they? Student: Yeah, but I really love competing, so… Professor: You know, I played soccer in college and my biggest challenge, and I didn’t always succeed, was getting my studying in during soccer season. Are you having a similar? Student: No. I really do make time to study, and I actually study more for this class than I do for all my other classes. But I didn’t see the grade I expected on my mid-term exam which is why I came by. Professor: Well, you didn’t do badly on the exam but I agree it did not reflect your potential. I say this because your work on the lab project was exemplary. I was so impressed with the way you handled the microscope and the samples of onion cells and, well, how careful you observed and diagramed and interpreted each stage of cell division, and I don’t think you could have done that if you hadn’t understood the chapter. I mean, it seemed you really had a good understanding of it. Student: I thought so, too. But I missed some questions about cell division on the exam. Professor: So, what happened? Student: I just sort of blanked out, I guess. I had a hard time remembering details. It was so frustrating. Professor: All right. Let’s back up. You say you studied. Where? At home? Student: At my kitchen table, actually. Professor: And that’s supposed to be a quiet environment? Student: Not exactly. My brother and parents try to keep it down when I’m studying but the phone pretty much rings off the hook, so. Professor: So you might try a place with fewer distractions, like, the library. Student: But the library closes at midnight and I like to study all night before a test. You know, so everything is fresh in my mind. I studied six straight hours the night before the mid-term exam. That’s why I expected to do so much better. Professor: Oh, OK. You know that studying six consecutive hours is not equivalent to studying one hour a day for six days. Student: It isn’t? Professor: No, there’s a research that shows that after an hour of intensive focus, your brain needs a break. It needs to, you know, shift gears a little. Your brain’s ability to absorb information starts to decline after about the first hour. So if you are dealing with a lot of new concepts and vocabulary, anyway, if you just review your notes even twenty minutes a day, it’d be much better than waiting until the night before the exam to try and absorb all those details. Student: Oh, I didn’t realize. Professor: Think of your brain as a muscle. If you didn’t practice regularly with your track team, and then try to squeeze in three weeks’ worth of running practice the day before a track meet, how well do you think you will perform in the races? 托福TPO15听力Conversation2题目 1.Why does the woman go to see her professor? A. To tell him about an athletic achievement. B. To find out the best approach to studying for a test. C. To ask a question about a laboratory project.。
TPO15听力解析
TPO15 listening 问题解析注：问题中红色标记词汇为解题突破点和关键词。
Section 1TPO15-L1 Conversation 11. Why does the student go to the campus newspaper office?O To turn in outlines of possible articlesO To find out when his article will be printed in the newspaperO To find out if he got a position as a reporterO To get help with an assignment for his journalism class答案：C解析：男学生报名做reporter，写好的outline一周前已经提交，但是没有收到答复，他来看一下情况。
原文如下：I sent them in about a week ago, but I haven't heard anything back yet, so, so I thought I'd stop by and see, but I guess you haven't looked at them yet2. Why does the student want to write for the campus newspaper?O He wants to earn some money.O He wants to learn about the newspaper business.O He wants to share his enthusiasm for physics.O He thinks the experience will be valuable.答案：D解析：男学生知道当reporter是没有报酬的，但是这有利于他写个人经历，比较重要。
托福备考托福阅读34套TPO样题+解析+译文15--2 Mass Extinctions物种灭绝
托福考试 复习托福阅读TPO15(试题+答案+译文)第2篇:Mass Extinctions物种灭绝托福阅读原文【1】Cases in which many species become extinct within a geologically short interval of time are called mass extinctions. There was one such event at the end of the Cretaceous period(around 70 million years ago). There was another, even larger, mass extinction at the end of the Permian period (around 250 million years ago). The Permian event has attracted much less attention than other mass extinctions because mostly unfamiliar species perished at that time.【2】The fossil record shows at least five mass extinctions in which many families of marine organisms died out. The rates of extinction happening today are as great as the rates during these mass extinctions. Many scientists have therefore concluded that a sixth great mass extinction is currently in progress.【3】What could cause such high rates of extinction? There are several hypotheses, including warming or cooling of Earth, changes in seasonal fluctuations or ocean currents, and changing positions of the continents. Biological hypotheses include ecological changes brought about by the evolution of cooperation between insects and flowering plants or of bottom-feeding predators in the oceans. Some of the proposedmechanisms required a very brief period during which all extinctions suddenly took place; other mechanisms would be more likely to have taken place more gradually, over an extended period, or at different times on different continents. Some hypotheses fail to account for simultaneous extinctions on land and in the seas. Each mass extinction may have had a different cause.Evidence points to hunting by humans and habitat destruction as the likely causes for the current mass extinction.【4】American paleontologists David Raup and John Sepkoski, who have studied extinction rates in a number of fossil groups, suggest that episodes of increased extinction have recurred periodically, approximately every 26 million years since the mid-Cretaceous period. The late Cretaceous extinction of the dinosaurs and ammonoids was just one of the more drastic in a whole series of such recurrent extinction episodes. The possibility that mass extinctions may recur periodically has given rise to such hypotheses as that of a companion star with along-period orbit deflecting other bodies from their normal orbits, making some of them fall to Earth as meteors and causing widespread devastation upon impact.【5】Of the various hypotheses attempting to account for the late Cretaceous extinctions, the one that has attracted the most attention in recent years is the asteroid-impact hypothesis first suggested by Luis andWalter Alvarez. According to this hypothesis, Earth collided with an asteroid with an estimated diameter of 10kilometers, or with several asteroids, the combined mass of which was comparable. The force of collision spewed large amounts of debris into the atmosphere, darkening the skies for several years before the finer particles settled. The reduced level of photosynthesis led to a massive decline in plant life of all kinds, and this caused massive starvation first of herbivores and subsequently of carnivores. The mass extinction would have occurred very suddenly under this hypothesis.【6】One interesting test of the Alvarez hypothesis is based on the presence of the rare-earth element iridium (Ir).Earth’s crust contains very little of this element, but most asteroids contain a lot more. Debris thrown into the atmosphere by an asteroid collision would presumably contain large amounts of iridium, and atmospheric currents would carry this material all over the globe. A search of sedimentary deposits that span the boundary between the Cretaceous and Tertiary periods shows that there is a dramatic increase in the abundance of iridium briefly and precisely at this boundary. This iridiumanomaly offers strong support for the Alvarez hypothesis even though no asteroid itself has ever been recovered.【7】An asteroid of this size would be expected to leave an immense crater, even if the asteroid itself was disintegrated by the impact. The intenseheat of the impact would produce heat-shocked quartz in many types of rock. Also, large blocks thrown aside by the impact would form secondary craters surrounding the main crater.To date, several such secondary craters have been found along Mexico’s Yucatan Peninsula, and heat-shocked quartz has been found both in Mexico and in Haiti.A location called Chicxulub, along the Yucatan coast, has been suggested as the primary impact site.托福阅读试题1.Paragraph 1 supports which of the following statements about mass extinctions?A.They take place over a period of 70 million years.B.They began during the Cretaceous period.C.They eliminate many animal species that exist at the time they occur.D.They occur every 250 million years.2.According to paragraph 2, scientists base their belief that a mass extinction is going on at present on which of the following?A.The speed with which mass extinctions are happening today is similar to the speed of past extinctions.B.The number of species that have died out since the last extinction event is extremely large.C.Mass extinctions occur with regularity and it is time for another one.D.Fossil records of many marine species have disappeared.3.The word extended in the passage is closest in meaning toA.specific.B. unlimited.C.reasonable.D. long.4.According to paragraph 3, each of the following has been proposed asa possible cause of mass extinctions EXCEPTA.habitat destruction.B.continental movement.C.fierce interspecies competition.D.changes in Earth's temperature.5.Paragraph 3 supports which of the following ideas about mass extinctions?A.Scientists know the exact causes of most mass extinctions.B.Mass extinctions are unlikely to happen again in the future.C.Insects, flowering plants, and bottom-feeding predators in the oceans tend to be the first organisms to disappear during episodes of mass extinctions.D.Some mass extinctions occurred on land and in the seas at the same time.6.Which of the sentences below best expresses the essential information in the underlined sentence （Paragraph 4）in the passage? Incorrect choices change the meaning in important ways or leave out essential information.A.Based on their studies of extinction rates of numerous fossil groups, paleontologists David Raup and John Sepkoski have determined that mass extinctions occur about every 26 million years.B.David Raup and John Sepkoski studied extinction rates of numerous fossil groups and suggest that mass extinctions during the Cretaceous period continued for 26 million years.C.Studies that paleontologists David Raup and John Sepkoski conducted of various fossil groups have revealed that extinction rates have increased over the past 26 million years.D.The studies conducted by paleontologists David Raup and John Sepkoski of the fossil remains of species suggest that the extinction rate of species started to increase by the middle of the Cretaceous period. 7.According to paragraph 4, what aspect of extinction episodes does the companion-star hypothesis supposedly clarify?A.Their location.B.Their frequency.C.Their duration.D.Their severity.8.The phrase account for in the passage(Paragraph 5)is closest in meaning toA.describe.B.challenge.C.explain.D.test.9.According to paragraph 6, what made iridium a useful test of the Alvarez hypothesis?A.Its occurrence in a few locations on Earth against several locations on other planets.B.Its occurrence in limited quantities on Earth against its abundance in asteroids.C.Its ability to remain solid at extremely high temperatures.D.Its ease of detection even in very small amounts.10.In stating that no asteroid itself has ever been recovered, the author emphasizes which of the following?A.The importance of the indirect evidence for a large asteroid.B.The fact that no evidence supports the asteroid impact hypothesis.C.The reason many researchers reject the Alvarez hypothesis.D.The responsibility of scientists for not making the effort to discover the asteroid itself.11.The word intense（Paragraph 7）in the passage is closest in meaningtoA.sudden.B.unusual.C.immediate.D. extreme.12.What is the purpose of paragraph 7 in the passage?A.It proposes a decisive new test of the Alvarez hypothesis.B.It presents additional supporting evidence for the Alvarez hypothesis.C.It explains why evidence relating to the Alvarez hypothesis is hard to find.D.It shows how recent evidence has raised doubts about the Alvarez hypothesis.13. Look at the four squares [■] that indicate where the following sentence could be added to the passage. Where would the sentence best fit? In general, it is believed that these two extinctions resulted from drastic environmental changes that followed meteorite impacts or massive volcanic eruptions.■Cases in which many species become extinct within a geologically short interval of time are called mass extinctions. ■There was one such event at the end of the Cretaceous period (around 70 million years ago). ■There was another, even larger, mass extinction at the end of the Permian period (around 250 million years ago). ■The Permian event has attracted muchless attention than other mass extinctions because mostly unfamiliar species perished at that time.14. Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points.There have been many attempts to explain the causes of mass extinctions.A.Asteroid impacts, evolutionary developments, and changes in Earth's climate and in the positions of the continents have all been proposed as possible causes of mass extinctions.B.Researchers have observed 26-million-year cycles in extinction rates of a number of fossil groups that could all be attributed to the same cause.C.According to the Alvarez hypothesis, much of the iridium originally present on Earth was thrown into the atmosphere as a result of an asteroid impact that also caused a mass extinction.D.The unusual distribution of iridium on Earth and the presence of craters and heat-shocked quartz are central to the theory that an asteroid impact caused the late Cretaceous event.E.The collision between Earth and a large asteroid resulted in massive damage and generated enough heat to cause irreversible changes inEarth's atmosphere.F.There was a particularly large mass extinction that occurred around 250 million years ago at the end of the Permian period, whose cause could not be determined.托福阅读答案1.以mass extinctions做关键词定位至第一句，说大量生物在短时间内灭绝的这种现象叫做大灭绝事件，C是原文的同义替换，所以是正确答案。
托福听力TPO学习宝典
Solution No.2
TheEffect of mountains and lands,i.e. Topography
Lake-effect snow
E.G. Great Lakes
The forming of clouds
The forming of snow
Closing
Talk to the boss
TPO18conversation1student—administrator—help
Structure
Student
Librarian
Opening
Transfer from Chicago
Interested intheprogram
International studies
TPO 20 conversation 1 Student—Librarian—help
Structure
Student
Librarian
Opening
Problem
Asked to return the book
To keep the book for thesis
Backgrounddetails
Prominentalumni
Advanced math course
TPO 21conversation 2student—professor—question
Structure
Student
Librarian
Opening
Learn a lot from the lecture
Work in the field
TPO文章结构—conversation
托福TPO15
TPO15-1-1 原文：A Warm-Blooded TurtleWhen it comes to physiology, the leatherback turtle is, in some ways, more like a reptilian whale than a turtle. It swims farther into the cold of the northern and southern oceans than any other sea turtle, and it deals with the chilly waters in a way unique among reptiles.A warm-blooded turtle may seem to be a contradiction in terms. Nonetheless, an adult leatherback can maintain a body temperature of between 25 and 26°C (77-79°F) in seawater that is only 8°C (46.4°F). Accomplishing this feat requires adaptations both to generate heat in the turtle’s body and to keep it from escaping into the surrounding waters. Leatherbacks apparently do not generate internal heat the way we do, or the way birds do, as a by-product of cellular metabolism. A leatherback may be able to pick up some body heat by basking at the surface; its dark, almost black body color may help it to absorb solar radiation. However, most of its internal heat comes from the action of its muscles.Leatherbacks keep their body heat in three different ways. The first, and simplest, is size. The bigger the animal is, the lower its surface-to-volume ratio; for every ounce of body mass, there is proportionately less surface through which heat can escape. An adult leatherback is twice the size of the biggest cheloniid sea turtles and will therefore take longer to cool off. Maintaining a high body temperature through sheer bulk is called gigantothermy. It works for elephants, for whales, and, perhaps, it worked for many of the larger dinosaurs. It apparently works, in a smaller way, for some other sea turtles. Large loggerhead and green turtles can maintain their body temperature at a degree or two above that of the surrounding water, and gigantothermy is probably the way they do it. Muscular activity helps, too, and an actively swimming green turtle may be 7°C (12.6°F) warmer than the waters it swims through.Gigantothermy, though, would not be enough to keep a leatherback warm in cold northern waters. It is not enough for whales, which supplement it with a thick layer of insulating blubber (fat). Leatherbacks do not have blubber, but they do have a reptilian equivalent: thick, oil-saturated skin, with a layer of fibrous, fatty tissue just beneath it. Insulation protects the leatherback everywhere but on its head and flippers. Because the flippers are comparatively thin and blade-like, they are the one part of the leatherback that is likely to become chilled. There is not much that the turtle can do about this without compromising the aerodynamic shape of the flipper. The problem is that as blood flows through the turtle’s flippers, it risks losing enough heat to lower the animal’s central body temper ature when it returns. The solution is to allow the flippers to cool down without drawing heat away from the rest of the turtle’s body. The leatherback accomplishes this by arranging the blood vessels in the base of its flipper into a countercurrent exchange system.In a countercurrent exchange system, the blood vessels carrying cooled blood from the flippers run close enough to the blood vessels carrying warm blood from the body to pick up some heat from the warmer blood vessels; thus, the heat is transferred from the outgoing to the ingoing vessels before it reaches the flipper itself. This is the same arrangement found in an old-fashioned steam radiator, in which the coiled pipes pass heat back and forth as watercourses through them. The leatherback is certainly not the only animal with such an arrangement; gulls have a countercurrent exchange in their legs. That is why a gull can stand on an ice floe without freezing.All this applies, of course, only to an adult leatherback. Hatchlings are simply too small to conserve body heat, even with insulation and countercurrent exchange systems. We do not know how old, or how large, a leatherback has to be before it can switch from a cold-blooded to a warm-blooded mode of life. Leatherbacks reach their immense size in a much shorter time than it takes other sea turtles to grow. Perhaps their rush to adulthood is driven by a simple need to keep warm.---------------------------------------------------------------------------------------------------------------Paragraph 1: When it comes to physiology, the leatherback turtle is, in some ways, more like a reptilian whale than a turtle. It swims farther into the cold of the northern and southern oceans than any other sea turtle, and it deals with the chilly waters in a way unique among reptiles.1. The phrase “unique among” in the passage is closest in meaning to○natural to○different from all other○quite common among○familiar to2. What can be inferred about whales from paragraph 1?○They are considered by some to be reptiles.○Their bodies are built in a way that helps them manage extremely cold temperatures.○They are distantly related to leatherback turtles.○They can swim farther than leatherback turtles.Paragraph 2: A warm-blooded turtle may seem to be a contradiction in terms. Nonetheless, an adult leatherback can maintain a body temperature of between 25 and 26°C (77-79°F) in seawater that is only 8°C (46.4°F). Accomplishing this feat requires adaptations both to generate heat in the turtle’s body and to keep it from escaping into the surrounding waters. Leatherbacks apparently do not generate internal heat the way we do, or the way birds do, as a by-product of cellular metabolism. A leatherback may be able to pick up some body heat by basking at the surface; its dark, almost black body color may help it to absorb solar radiation. However, most of its internal heat comes from the action of its muscles.3. The word “feat” in the passage is closest in meaning to○remarkable achievement○common transformatio n○daily activity○complex solution4. Paragraph 2 mentions all of the following as true about the body heat of adult leatherback turtles EXCEPT:○Their muscles produce heat for maintaining body temperature.○Their dark bodies help trap solar radiation.○Their cellular metabolism produces heat as a by-product.○Basking at the water’s surface helps them obtain heat.Paragraph 3: Leatherbacks keep their body heat in three different ways. The first, and simplest, is size. The bigger the animal is, the lower its surface-to-volume ratio; for every ounce of body mass, there is proportionately less surface through which heat can escape. An adult leatherback is twice the size of the biggest cheloniid sea turtles and will therefore take longer to cool off. Maintaining a high body temperature through sheer bulk is called gigantothermy. It works for elephants, for whales, and, perhaps, it worked for many of the larger dinosaurs. It apparently works, in a smaller way, for some other sea turtles. Large loggerhead and green turtles can maintain their body temperature at a degree or two above that of the surrounding water, and gigantothermy is probably the way they do it. Muscular activity helps, too, and an actively swimming green turtle may be 7°C (12.6°F) warmer than the waters it swims through.5. The word “bulk” in the passage is closest in meaning to○strength○effort○activity○massParagraph 4: Gigantothermy, though, would not be enough to keep a leatherback warm in cold northern waters. It is not enough for whales, which supplement it with a thick layer of insulating blubber (fat). Leatherbacks do not have blubber, but they do have a reptilian equivalent: thick, oil-saturated skin, with a layer of fibrous, fatty tissue just beneath it. Insulation protects the leatherback everywhere but on its head and flippers. Because the flippers are comparatively thin and blade-like, they are the one part of the leatherback that is likely to become chilled. There is not much that the turtle can do about this without compromising the aerodynamic shape of the flipper. The problem is that as blood flows through the turtle’s flippers, it risks losing enough heat to lower the animal’s central body temperature when it returns. The solution is to allow the flippers to cool down without drawing heat away from the rest of the turtle’s body. The leatherback accomplishes this by arranging the blood vessels in the base of its flipper into a countercurrent exchange system.6. The word “it” in paragraph 4 refers to○the problem○blood○the turtle○body temperature7. According to paragraph 4, which of the following features enables the leatherback turtle to stay warm?○An insulating laye r of blubber○A thick, oily skin covering fatty tissue○The aerodynamic shape of its flippers○A well-insulated headParagraph 5: In a countercurrent exchange system, the blood vessels carrying cooled blood from the flippers run close enough to the blood vessels carrying warm blood from the body to pick up some heat from the warmer blood vessels; thus, the heat is transferred from the outgoing to the ingoing vessels before it reaches the flipper itself. This is the same arrangement found in an old-fashioned steam radiator, in which the coiled pipes pass heat back and forth as water courses through them. The leatherback is certainly not the only animal with such an arrangement; gulls have a countercurrent exchange in their legs. That is why a gull can stand on an ice floe without freezing.8. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.○In a turtle's countercurrent exchange system, outgoing vessels lie near enough to ingoing ones that heat can be exchanged from the former to the latter before reaching the turtle's flippers.○Within the turtle's flippers, there is a countercurrent exchange system that allows colder blood vessels to absorb heat from nearby warmer blood vessels and then return warmed blood to the turtle's body.○In a countercurrent exchange system, a turtle can pick up body heat from being close enough to other turtles, thus raising its blood temperature as it passes them.○When a turtle places its flippers close to its body, it is able to use its countercurrent exchange system to transfer heat from the warmer blood vessels in its body to the cooler blood vessels in its flippers.9. Why does the author mention old-fashioned steam radiator in the discussion of countercurrent exchange systems?○To argue that a turtle's central heating system is not as highly evolved as that of other warmblooded animals○To provide a useful comparison with wh ich to illustrate how a countercurrent exchange system works○To suggest that steam radiators were modeled after the sophisticated heating system of turtles○To establish the importance of the movement of water in countercurrent exchange systems10. The phrase “courses through” in the passage is closest in meaning to○rises through○heats up in○runs through○collects inParagraph 6: All this applies, of course, only to an adult leatherback. Hatchlings are simply too small to conserve body heat, even with insulation and countercurrent exchange systems. We do not know how old, or how large, a leatherback has to be before it can switch from a cold-blooded to a warm-blooded mode of life. Leatherbacks reach their immense size in a much shorter time than it takes other sea turtles to grow. Perhaps their rush to adulthood is driven by a simple need to keep warm.11. According to paragraph 6, which of the following statements is most accurate about young leatherback turtles?○They lack the countercurrent excha nge systems that develop in adulthood.○Their rate of growth is slower than that of other sea turtles.○They lose heat easily even with insulation and countercurrent exchange systems.○They switch between cold-blooded and warm-blooded modes throughout their hatchling stage.Paragraph 3: Leatherbacks keep their body heat in three different ways. The first, and simplest, is size. The bigger the animal is, the lower its surface-to-volume ratio; for every ounce of body mass, there is proportionately less surface through which heat can escape. An adult leatherback is twice the size of the biggest cheloniid sea turtles and will therefore take longer to cool off. Maintaining a high body temperature through sheer bulk is called gigantothermy. ■It works for elephant s, for whales, and, perhaps, it worked for many of the larger dinosaurs. ■It apparently works, in a smaller way, for some other sea turtles. ■Large loggerhead and green turtles can maintain their body temperature at a degree or two above that of the surrou nding water, and gigantothermy is probably the way they do it. ■Muscular activity helps, too, and an actively swimming green turtle may be 7°C (12.6°F) warmer than the waters it swims through.12. Look at the four squares [■] that indicate where the follo wing sentence could be added to the passage.However, these animals have additional means of staying warm.Where would the sentence best fit?13. Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points.Contrary to what we would expect of reptiles, the leatherback turtle is actually warm-blooded.●The leatherback turtle uses a…●The leatherback turtle is…●Leatherbacks have an…Answer Choices○Even though they swim into cold ocean waters,leatherbacks maintain their body heat in much the same way as sea turtles in warm southern oceans do.○The leatherback turtle uses a countercurrent exchange system in order to keep the flippers from drawing heat away from the rest of the body.○The shape of the leatherback turtle's flippers is especially important in maintaining heat in extremely cold northern waters.○The leatherback turtle is able to maintain body heat through sheer size.○Leatherbacks have an insulating layer that can be considered the reptilian version of blubber.○Young leatherbacks often do not survive to adulthood because they are not able to switch from a cold-blooded way of life to a warm-blooded one quickly enough.---------------------------------------------------------------------------------------------------------------参考答案：1. ○22. ○23. ○14. ○35. ○46. ○27. ○28.○19. ○210. ○311. ○312. ○413. The leatherback turtle uses a…The leatherback turtle is…Leatherbacks have an…--------------------------------------------------------------------------------------------------------------- 答案解析：B，词汇题。
托福TPO15口语Task2题目+满分范文
为了帮助大家高效备考托福，为大家带来托福TPO15口语Task2题目+满分范文，希望对大家备考有所帮助。
托福TPO15独立口语Task2题目： Question Do you agree or disagree with the following statement? It is important to remember and learn from the past. Use details and examples to explain your opinion. 托福TPO15独立口语Task2满分范文： I totally agree with this statement that it’s important to remember and learn from the past.We all make mistakes and we all have to remember mistakes. Because mistakes tell us what isn’t right. For example, when I was in the first grade primary school, I took a toy car from another student without informing him. I was too young to know that taking things from others without mentioning isn’t right. Then my teacher helped the other student find this toy car and labeled me as a thieve. I didn’t realize how serious this matter was until my father told me that this was humiliating.I swore to myself that I would never take anything from others without informing the owners. I think this is a valuable lesson and I’ll remember it forever. 以上是给大家整理的托福TPO15口语Task2题目+满分范文，希望对你有所帮助!。
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【托福听力资料】托福TPO15 听力文本-Lecture 4众所周知，托福TPO材料是备考托福听力最好的材料。
相信众多备考托福的同学也一直在练习这套材料，那么在以下内容中我们就为大家带来托福TPO听力练习的文本，希望能为大家的备考带来帮助。
TPO 15 Lecture 4 BiologyNarrator: Listen to part of a lecture in a biology class.Professor:OK. We’ve been talking till now about the two basic needs of a biologicalcommunity – an energy source to produce organic materials, you know uh, food forthe organisms, and the waste recycling or breakdown of materials back intoinorganic molecules, and about how all this requires photosynthesis when greenplants or microbes convert sunlight into energy, and also requiresmicroorganisms, bacteria, to secrete chemicals that break down or recycle theorganic material to complete the cycle. So, now we are done with this chapter ofthe textbook, we can just review for the weekly quiz and move on to the nextchapter, right? Well, not so fast. First, I ‘d like to talk about somediscoveries that have challenged one of these fundamental assumptions about whatyou need in order to have a biological community.And, well, there actually were quite a few surprises. It all began in 1977with the exploration of hydrothermal vents on the ocean floor. Hydrothermalvents are cracks in the Earth’s surface that occur, well, the ones we aretaiking about here are found deep at the bottom of the ocean. And these vents onthe ocean floor, they release this incredibly hot water, 3 to 4 times the temperature that you boil water at, because this water has been heated deep within the Earth.Well about 30 years ago, researchers sent a deep-sea vessel to explore the ocean’s depth, about 3 kilometers down, way deep to the ocean floor, No one had ever explored that far down before. Nobody expected there to be any life down there because of the conditions.First of all, sunlight doesn’t reach that far down so it ’ s totally dark. There couldn’t be any plant or animal life since there’s no sunlight, no source of energy to make food. If there was any life at all, it’d just be some bacteria breaking down any dead materials that might have fallen to the bottom of the ocean . And?Student 1 ：And what about the water pressure? Didn ’ t we talk before about how the deeper down into the ocean you go, the greater the pressure? Professor ：Excellent point! And not only the extreme pressure, but also the extreme temperature of the water around these vents. If the lack of sunlight didn’t rule out the existence of a biological community down there then these factors certainly would, or so they thought.Student 2：So you are telling us they did find organisms that could live under those conditions?Professor: They did indeed, something like 300 different species.Student 1 ：But... but how could that be? I mean without sunlight, no energy,no no …Protessor:What they discovered was that microorganisms, bacteria, had taken over both functions of the biological community - the recycling of waste materials and the production of energy. They were the energy source. You see, it turns out that certain microorganisms are chemosynthetic - they don’t need sunlight because they take their energy from chemical reactions.So, as I said, unlike green plants which are photosynthetic and get their energy from sunlight, these bacteria that they found at the ocean floor, these are chemosynthetic, which means that they get their energy from chemical reactions. How does this work?As we said, these hydrothermal vents are releasing into the ocean depth this intensely hot water and here is the thing, this hot water contains a chemical called hydrogen sulfide, and also a gas , carbon dioxide. Now these bacteria actually combine the hydrogen sulfide with the carbon dioxide and this chemical reaction is what produces organic material which is the food for larger organisms. The researchers had never seen anything like it before.Student 2 : Wow! So just add a chemical to a gas, and bingo, you ’ ve got a food supply?ProfessorNot just that! W hat was even more surprising were all the large organisms that lived down there. The most distinctive of these was something called thetube worm. Here, let me show you a picture . The tube of the tube worm is really, really long. They can be up to one and a half meters long , and these tubes are attached to the ocean floor, pretty weird looking, huh?And another thing, the tube worm has no mouth or digestive organs. So you are asking how does it eat? Well, they have these special organs that collect the hydrogen sulfide and carbon dioxide and then transfer it to another organ, where billions of bacteria live. These bacteria that live inside the tube worms, the tube worms provide them with hydrogen sulfide and carbon dioxide. And the bacteria, well the bacteria kind of feed the tube worms through chemosynthesis, remember, that chemical reaction I described earlier.。