Unit 1 -7 教参
《典范英语》(1a-L7)教学参考

《典范英语》(1a-L7)教学参考Is it?教学参考的目的在于为实验课提供一个基本的思路和框架,帮助实验教师更好地把握课题理念。
课题组鼓励实验教师结合学生的实际情况适当做出调整,将实验课上出特色。
一、教学目标1. 语言能力目标:学生能够读懂故事情节;惟妙惟肖地模仿录音;绘声绘色地独立朗读故事;能够灵活运用“Is it…?”和“It is….”;体会朗读一般疑问句与陈述句时的不同语调;掌握“Is it”和“It is”的连读。
2. 非语言能力目标:让学生体会一家人在后院玩游戏时的快乐氛围;培养学生观察人物细节从而猜测人物是谁的能力;通过让学生画画来培养学生的动手能力和想象力。
二、课时安排要求每周不少于两课时,每课时至少完成一个故事。
三、教师要求1. 教师课前须熟读故事,了解故事内容。
2. 对于较难的单词,教师可板书,并配合动作和表情帮助学生理解。
3. 全英文授课。
四、教学用具多媒体设备、CD机、课件(课题组提供)、不透明的盒子1个、熟鸡蛋1个(可选其他物品)、人物图(Mum, Dad, Chip, Biff, Kipper, Floppy)、句卡(故事中的8句原文)。
五、课堂教学基本步骤1. 导入(Lead-in):通过让学生猜测物品,激发学生兴趣,导入故事通过师生互动的小游戏,引导学生猜测物品,为进入故事情境做铺垫。
教师事先将准备好的熟鸡蛋放入不透明盒子中,让学生听一听、摸一摸,并提问简单的问题与学生互动:Let’s play a game “Guess! Guess!”.Look, what is it? (教师手拿盒子向学生提问)It is a box.What’s in the box? (教师摇晃盒子发出响声)Guess! Guess!You can touch it. Is it a pancake? (教师走到一个学生面前,让他把手伸到盒子里摸一摸)You can touch it. Is it an apple? (教师走到另一个学生面前,让他把手伸到盒子里摸一摸)教师可多让几个学生摸一摸,猜一猜,以上环节可重复。
中职英语基础模块教案

Welcome to... Look at... Be glad to do... A lot of... Thank...for...
Next to... There be... ...be glad to do... Do you see...?
句子:
1.Welcome to Xinhua Vocational School.
b.Good morning(afternoon,evening).---Good morning(afternoon,evening).
c.How do you do?---How do you do?
d.How are you?---Fine,thank you.
e.Glad to meet you.---Glad to meet you.
五、Summarize
总结Unit 1中重点单词、句子、语法。
六、Homework
Preview Unit 2.
教学过程设计:
一、Check (10mins)
Check the homework.
二、Review (10mins)
1. Reviewgrammar.
2. Reviewthe text and write the Reading Comprehensive Part.
从整体情况看,掌握程度一般。
授课类型
请标注●
理论课〔●〕上机课〔〕实验课〔〕习题课〔〕其他〔〕
教学目的、要求〔分掌握、熟悉、了解三个层次〕:
掌握短语和句型的用法、熟悉元音音标、了解国际音标。
教学重点及难点:
所学短语、句型的灵活运用。
教学基本内容
一、Check
Check the homework.
unit1教学设计七册 (1)

第二课时一、教学目标与要求1.能听、说、读、写四会掌握句子:“How do you go to school?Usually I go to school on foot.Sometimes I go by bike.”并能在情景中正确运用。
2.能够表述自己以何种方式上学并简单陈述原因,如:Usually I go to school by bus because it’s fast.3.能够听董Let’s try的录音内容并选出正确选项。
二、教学重、难点分析1.本课时的教学重点是听、说、读、写句型:How do you go to school?Usually Sometimes I go by…2.本课时的教学难点是学生书写四会句子并能简单陈述选择某种交通方式上学的原因。
三、课前准备1.教师准备录音机和本课时的录音带。
2.教师准备本单元A Let’s learn部分的单词卡片。
3.教师课前在一张纸上画出空白柱状图,用于统计班内学生上学方式的调查4.学生每人准备一张卡片,画一个印象最深刻的交通标志。
四、教学步骤和建议1.热身(Warm-up)(1)师生对话,复习上一课时内容,比如:“Good morning!How do you go to schooltoday?What about you?Do you go by bus,too?”然后学生复习Let’s chant部分的歌谣。
(2)Let’s sing教师放c Let’s sing部分的歌曲“How Do You Go toSchool?”第一遍学生听并轻声跟唱。
第二遍学生跟录音大声唱一遍。
2.预习(Preview)(1)教师出示单词卡片,提问:“How d0 you go to school?”学生根据图片内容回答:“I go to schoolby…”师生会话直到班级里大部分学生能够准确说出图中交通工具的名称以及该句型。
然后学生两人一组用单词卡片练习句型:“How do yougo to school?I g0 t0 school by…”教师对表达仍有困难的学生给予个别辅导。
英语1 unit7 教案

A: Hello!
B: Hello! This is …. Can/May I speak to ….?
A: This is … speaking. ….isn’t in at the moment. Can /May I take a message?
B: Ok, thanks.
A: All right, I’ll tell him / her.
3.学生能根据常用打电话句型,开展相关打电话讲述正在干什么事的对话
教学重点
( 1 )通过学习打电话的对话,让学生掌握常用打电话语句。
( 2 )在打电话对话教学中渗透现在进行时的学习
教学难点
( 1 )学生记住关于运动项目的单词
( 2 )学生听懂有关打电话对话中的详细内容学生听懂有关进行体育活动的打电话内容
To: Tom
Things: come to school to watch the basketball match this evening
To: Jane
Things: come to the playground to play volleyball together this afternoon
B: Thank you. Bye!
2. Performance: Make a call
Teacher explains the rule: Make a phone call to your friend to invite him or her to take part in a sport item. But he/she is not in when you call. And his/her father answers the phone. The cards with sentences and words on the blackboard will help you to finish the dialogue.
Book7 Unit1教案

选修7unit1 Living Well单元教案马晓露一教材分析本单元以残疾及残疾人生活为中心,介绍了一些残疾人凭借顽强的毅力和社会的关爱克服生活中的种种困难,以积极的态度面对人生的挑战。
通过本单元的学习,提高学生理解、尊重、关心、帮助残疾人意识,使残疾人与健全人一样共享美好生活。
这是对新课程目标中情感态度与价值观培养目标的全方位体现。
二教学目标1. 知识目标a. 掌握以下重点词汇和短语ambition, disability, fellow, independent, beneficial, encouragement, in other words, all in all, out of breath, make fun of.b. 理解和运用以下重点句型1. I have to adapt to my disability.2. Just accept them for whom they are and give them encouragement to live as rich and full a life as you do.2. 能力目标a. 通过对段落结构的分析,使学生掌握scanning的阅读技巧。
要提高他们的阅读速度和快速寻找信息的能力,培养他们的分析和概括能力。
b. 让学生理解残疾人及其生活情况,使学生明白身体有残疾并不意味着生活不如意,但他们在日常生活和工作中比健全人面临着更大的挑战。
3.情感目标提高学生理解、尊重、关心和帮助残疾人意识。
加强合作意识、陶冶情操,培养正确的审美观和价值观。
三教学重点与难点1.教学重点:重点词汇句型的掌握2.教学难点:帮助学生理解残疾人所面临的种种困难,增强学生的同情心与爱心,引导他们珍惜时间,珍惜生活。
教学过程四教学方法任务型学习法多媒体辅助法合作性学习法Warming up,pre-reading and reading部分教学过程Step 1Warming up1.Warming up by discussingFirst ask students to talk about people with a mental or physical disability to seehow much they know about disabilities. Students will be asked to discuss the following questions in small groups.Do you know any famous people who are disabled?What difficulties do they have to overcome in daily life?What have they achieved?Suggested answers:Steven Hawking has a muscle disease,but he makes great contributions in science and puts forward his theory about black holes.Beethoven was deaf in one ear when he was 26 and totally deaf at the age of 35,but he was a great composer.Helen Keller was deaf and blind,but she was a great writer.2.Warming up by talkingFirst,ask students to look at the pictures and read what these people have achieved even though they each have a disability.Next,work with partners to talk about what disability they might have according to each description below the picture. Suggested answers:Rosalyn is in a wheelchair.She has walking difficulty.Richard has difficulty with eyesight,so he can't read the questions or write the answers for his college entrance exams.Sally has hearing problems (though not deaf as she can still understand loud speech in the cinema).Gao Qiang was born with Down's Syndrome,which is a mental disability.Some Doun's Syndrome Down's Sufferers have made a good career as actors.Step 2Pre-readingAsk students to read the short paragraph in Pre-reading carefully and find out the purpose of the website “Family Village”.Suggested answers:1.To give ordinary young people with a disability a chance to share their stories with others.2.To inspire other disabled people.3.To get non-disabled people to understand more about how challenging life can be for people with disabilities.Step 3Reading1.SkimmingGive students 2 minutes;ask them to read the passage fast to fill in the blanks:Sum up the main idea of each paragraph:Paragraph 1:A(n)______ to Marty and his muscle disease.Paragraph 2:How the disease ______.Paragraph 3:Marty met a lot of ______ at school.Paragraph 4:How his life has become ______.Paragraph 5:The ______ of his disease.Suggested answers:Paragraph 1:An introduction to Marty and his muscle disease.Paragraph 2:How the disease developed/started.Paragraph 3:Marty met a lot of difficulties at school.Paragraph 4:How his life has become easier.Paragraph 5:The advantages of his disease.2.Scanning for detailed informationAsk students to read the passage carefully to locate the detailed information.(1)First ask students to read paragraph1 and complete the chart below.Disease:Difficulties :Motto :Suggested answers:Disease: A muscle disease that makes him very weak.Difficulties:He can't run or climb stairs as quickly as other people.Sometimes he is clumsy and drop things or bump into furniture.Motto:L ive one day at a time.(2)Next read paragraph2 and paragraph3 and choose the best answer.Why did the doctors cut out a piece of muscle from Marty's leg?A.Because they could cure the disease by cutting it out.B.Because they wanted to use it as a specimen(标本).C.Because they would transplant(移植) the new muscle.D.Because they wanted to find out the cause of the disease.Key:D(3)Read paragraph4 and answer the following questions:①What is Marty's ambition?②What is Marty's achievement?③What is Marty's hobby?Suggested answers:①Marty's ambition is to work for a firm that develops computer software when he grows up.②Marty invented a computer football game and a big company decided to buy it from him.③As well as going to the movies and football matches with his friends,he spends a lot of time with his pets.He has two rabbits,a parrot,a tank full of fish and a tortoise.(4)Ask students to find Marty's advice in paragraph5.Suggested answers:Don't feel sorry for the disabled.Don't make fun of them.Don't ignore them.Accept them for who they are.Encourage them to live as rich and full a life as healthy people do.Step 4Consolidation1.Ask students to read the whole passage and choose the best answers.(1)Which of the following is false?A.Although there are a few students who look down upon him,Marty never gets annoyed.B.Marty leads a meaningful life and does not feel sorry for being disabled. C.Marty only spends time with his pets and never with his friends.D.Marty's disability has made him more independent.(2)From the passage we can infer that ______.A.Marty asks others to feel sorry for himB.Marty never loses heartC.Marty is afraid of being made fun ofD.Marty will not accept any encouragement because he has grown stronger psychologicallyKeys:(1)C(2)B2.Discuss in pairs to get the main idea of the passage by filling in the blanks. Though he is a ______ person,Marty never feels ______ for himself and he ______ his life.Suggested answers:disabled;sorry;enjoysStep 5Discussion1.Ask students to discuss the following questions in small groups.(1)How did Marty's feeling changed over time?(2)What kind of person do you think Marty is?Can you use adjective words to describe him?Suggested answers:(1)The change of Marty's feeling over time:hopeful→hopeless→stupid→not get annoyed→good/busy(2)We can see Marty is optimistic/brave/independent/strong/minded.Step 6Homework1.Retell Marty's Story after class.2.Surf the Internet to learn more about the life of disabled people.Language Study部分Teaching aims:1.To learn the useful expressions and sentence structures in the reading.2.To enable students to use language points.Teaching procedures(教学过程)Step 1Learning words and phrases1.ambition n.雄心,野心Her ambition is to become part of the national team for the next Paralympic Games. 她的抱负是能够成为国家队的一员来参加下一届残奥会。
人教版七年级英语教参

人教版七年级英语教参一、词汇部分。
1. 课本单词表。
- 重点单词的记忆方法,如利用音标、联想、分类等。
- 例如:“pencil”这个单词,根据音标[ˈpensl]来记忆,它属于文具类单词,可联想其他文具如pen、eraser等。
2. 常见词汇拓展。
- 形容词变副词(如quick - quickly)。
- 名词复数形式的特殊变化(如man - men,child - children)。
二、语法部分。
1. 一般现在时。
- 用法:表示经常发生的动作或存在的状态。
- 结构:- 主语为第三人称单数(he/she/it等)时,动词要用第三人称单数形式(如He likes reading.)。
- 主语为其他人称时,动词用原形(I like reading.)。
- 时间标志词:often,usually,sometimes等。
2. 名词的所有格。
- 有生命的名词所有格:- 单数名词加's(如Tom's book)。
- 以s结尾的复数名词加'(如the students' classroom)。
- 无生命的名词所有格:用“of+名词”结构(如the window of the room)。
三、听力与口语部分。
1. 听力技巧。
- 听前预测:根据题目和所给的提示信息,推测听力内容可能涉及的话题、人物、事件等。
- 听中注意关键词:像but,however等表示转折的词,以及数字、时间、地点等重要信息。
- 听后检查:根据听到的内容,检查答案是否符合逻辑。
2. 口语练习。
- 日常对话练习:课本中的对话场景,如问候、介绍、购物等,进行角色扮演。
- 发音练习:注意元音、辅音的发音,连读、弱读等语音现象。
例如,“I'm”的连读发音[ɑɪm]。
四、阅读部分。
1. 阅读技巧。
- 略读:快速浏览文章,了解文章的大致内容、主题和结构。
- 精读:仔细阅读文章,理解每个句子的含义,注意细节信息,如人物的特征、事件的经过等。
七年级英语Unit-1第七到第十课全部教案牛津版
七年级英语学科导学案 7A Unit 1 第十课时学习目标1.知识目标:(1) 本课时需要掌握的的词汇:dark CD (compact disc的缩写) lots of 和a lot of lesson(2) 其中出现的固定用法及句型结构 :like/love doing sth. ; be good at ; lots of 的用法。
2.能力目标:能够用英语做自我介绍。
3.情感目标:通过自我介绍同学之间互相了解,学会交友、互助。
学习重难点:(1)重点: 如何运用一些简单的英语句型句式进行自我介绍。
(2)难点:如何理解所给短文并能够掌握其中的一些词组和固定用法。
课前准备1. Preview the new words. (要求:独立认读每个生词;尝试写出本课每个生词的音标、词性和汉语意义)dark lesson someonesound great lots of2. Preview the new text. (要求:独立朗读、口译Main Task部分;尝试写出每个重、难点语句的汉语意义)_____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ ____________3.Try to complete Main Task of Workbook .(尝试完成同步辅导Main Task部分的练习)课内导学I.Leading in:Ask several students to greet with each other and introduce themselves before the class.Correct their mistakes in time.II.Reading materials:1.Ask the students to turn to Page 19 and read paragraph 1(a short paragraph about Millie).2.Play the tape for the students to listen and try to read it correctly.Then asksome of them to make a lead-reading for the students.3.Give the students some questions based on this passage and let them Answer according to the passage.Check up for necessary.(1) Where was Millie born ?(2) How old is Millie ?(3) What does he look like ?(4) What does he like doing at weekend ?(5) Where does study ?4.Do the second paragraph the same as the firt one.---The problems about this passage(Judge the following statements True or False)(1) Daniel was born in Beijing and lives in Nanjing now .(2) He is good at English .(3) He lives with his friends now.(4) He likes his classmates and they like him,too ?(5) Daniel is a tall and strong boy .III.Reviewing and Practising:1.Give the students enough time to read the two passages and try to recite them or say something about the two students.2.Ask the students to fill in the blanks with the right words acorrding to the passages.Millie is a middle school student in _____ _____ _____ School.He is ____and his eyes are _____.His hair is ____and ____.He likes _____ and ______. He is good at _______.His classmates all like to ____ ____ him.Daniel is_______years old .He is from _____.He likes _____ _____ ____very much .He is _____and ____.3.Give them a question to discuss and answer.____What kind of person are you ?IV.Fill in the blanks with the right word from the boxHelen is a student in a middle ______.She______often busy(忙)on weekdays.She and her classmates _____to school from Monday to Friday.After school ,she ___a lot of things to do .She likes _________basketball in the afternoon.She _____ or go to ____her grandmother at weekend.V. Write a passage using the given ingformation: Zhang liwen English name : Mike2. Age :133.Class and Grade :Class 7, Grade 84.Appearance: big eyes and black hair;tall and strong5.Address: On Beijing Road in Xuzhou6.Hobby: play footballand in the school team ;listen to music7.Best friends: Liu Hua , Li zhiguo ,Zhangxizhou , Chengyongsheng8.Hope: a great singer like Liu HuanHello ! I am Mike .My ________name is ________.I am a boy of ____years old.I am ______ and ______.I like __________football after school.It is my favourite sport.I have black _____and ________eyes.I like _____ to ____at weekend and I want to ______a great _____like Liu Huan some day.I live on ______Road in Xuzhou .Ihave many good friends at school ,they are ______ , Lizhiguo ,_______ and ______.I like them and they like me too.达标检测 (独立完成以下各题)[达标检测一](5分钟)7A Unit 1 第十课时姓名:班级:时间:2009年____月日等第 _______I. Translating exercises。
Unit1Lesson7全英文教案
Lesson 7: Don’t Fall off the PizzasTeaching Contents:Master words and expressions: result, none, fewTeaching Aims:1.Learn the spirit of Olympics.2.Make use of the spirit in class.Teaching Difficult Points:1.How to demonstrate something clearly.2.How to write e-mails.Teaching Difficult Points:The tense of Object Clause.Teaching Preparation: picturesTeaching Aids: audiotape, flashcards, picturesType of lesson: new lessonTeaching Procedure:the class into several groups and sum what we learned in this unit. Do you think what Jenny wrote in her diary?Let some students give their answers in front of the class.to the tape and answer the following questions:1.How many events did Jenny’s class invent?2.Whose invention did Jenny like best?Step3. Read the text and check the answers. Then encourage the students to ask more questions about this part. They can stand in front of the class and point out which student to answer the question.Step4. Make sentences with the language points: one by one, be fun, catch up with, think ofWe go into the classroom one by one.Playing football is fun.Nobody can catch up with me in the race.Who can think of better idea/Divide the class into several groups. Every group has the same people as other teams. We play a making sentences game with the four phrases. The team who finishes the work first is the winner. Step5. Use the same groups to read the text. Which team can finish the text first? Every group has a student to see if the others read the text correctly.Step6. Come to “LET’S DO IT’.Write e-mails to your pen pals. Try to finish the task in front of the class. Ask some students to present their e-mails in front of the class.Step7. Homework1.Finish off the activity book.2.Go on the next reading in the student book.Summary:The best way to learn a foreign language well is to use it. Give the students more time to practice in the class. The use of the teacher is to instruct them. Give them help when they are in trouble.Class is a large stage for the students to act.。
教参《英语 基础模块》上册 Unit 1
Useful Expressions
welcome to… look at… be glad to do… a lot of… thank … for … next to… This way, please. Here we are! How large it is! See you next time.
2)I’m very glad to meet you here today. 非常高兴今天在这里见到你们。 be glad to do … “很高兴做……”。又如:I’m glad to see you. 很高兴见到你。
3)There are a lot of books in it. 图书馆里有很多书。 句中 it 代替上句中的 library,这是代词 it 的用法之一。 a lot of… “很多,大量的”。又如:You can see a lot of cars in the street. 在街上, 你能见到许多汽车。
See you later! 一会儿见!See you tomorrow! 明天见!
4. 练习参考答案
1)Reading Comprehension 参考答案 Fill in the blanks with the right information from the text “Welcome to Our School” to complete the following statements.
4)Can you see a red building next to the library? 你能看见紧挨着图书馆的一栋红楼 吗? 这是情态动词开头构成的一般疑问句。 next to… “邻接着,紧挨着”。又如:The teachers’ room is next to our classroom. 教员室紧挨着我们的教室。
Unit-7
$10 $30
$3
$20 $18
$12 $55
Step 3 Practice
First give the students an example: ask a student some questions about her or his clothes: T: How much is your sweater? S: It’s…… T: How much are your shoes? S: They are…… Then let the students ask and answer in pairs. Give help when necessary. At last ask some pairs to act out their conversations.
Step 4 Listening practice
Listen to the tape and do 1b、2a and 2b.
Summary:
What is this? It’s a …. What color is it? It’s …. What are these? They’re …. What color are they? They’re…. How much is it? -It’s …. dollar(s)/yuan. How much are they? -They’re …dollar(s)/yuan
Step 5 Game
Show a picture with some clothes and their prices. Let students have a quick look. Then cover the prices, let the students guess the price by using “ How much is…? It’s … How much are…? They are …” The students who first guesses the right price will win the game. Give her or him a small gift.
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Unit 1 Sources of EnergyText APetroleumSentence structure analysis1. Instead of originating in accumulating woody matter, petroleum may be the product ofthe accumulating fatty matter of ocean organisms such as plankton, the myriads of single-celled creatures that float in the surface layer of the ocean. (Para.2) 石油,并不是来自于逐渐积聚的木质物质,而可能是来自于逐渐积聚的海洋生物的脂肪物质。
比如浮游生物:大量浮游在海水表层的单细胞生物。
这是一个简单句,主语petroleum,谓语动词may be,表语product,构成句子主干。
instead of 介词短语作状语,such as plankton是product一词的同位语,the myriads of single-celled creatures that float in the surface layer of the ocean是名词性短语,做plankton的同位语。
2. It is only necessary that the organisms settle down into the ooze underlying shallowarms of the ocean under conditions of oxygen shortage. (Para. 3) 生物有机体只需在缺氧的条件下沉积到海湾浅水处的淤泥里。
该句的框架为:it is +adj.+that从句,it做形式主语,真正的主语是that从句的内容。
现在分词短语underlying…做后置定语修饰ooze。
3.Toward the end of the nineteenth century, however, engines were developed which were powered by the explosions of mixtures of air and inflammable vapors within the cylinders. (Para. 9) 然而,到19世纪末人们研制出了内燃机。
内燃机是通过在汽缸里将空气与可燃气体混合,产生爆炸来提供动力的。
该句为复合句,句子的主干是engines are developed, which 引导的定语从句修饰先行词engines;toward the end of the nineteenth century介词短语作时间状语。
4.Such internal combustion engines are more compact than earlier steam engines and can be made to start at a moment’s notice, whereas steam engin es require a waiting period while the water reserve warms to the boiling point. (Para. 10) 这种内燃机与蒸汽机相比,机身小巧,可以瞬间启动;而蒸汽机需要一定时间,等待储水加热到沸点。
该句是由whereas连接的并列句;在前一个分句中包含and连接的两个并列成分,而后一个分句中包含while 引导的时间状语从句。
5. There is another complication in the fact that petroleum is not nearly so evenlydistributed as coal is. (Para. 14) 还有另一种复杂情况,即石油的分布不如煤的分布均匀。
该句的主句是There is another complication in the fact,that引导的是同位语从句,补充说明fact的内容。
6. Kuwait, for instance, which is a small nation at the head of the Persian Gulf, with anarea only three-fourths that of Massachusetts and a population of about half a million, possesses about one-fifth of all the known petroleum reserves in the world. (Para. 15) 例如,位于波斯湾岬角处的科威特,面积只有麻省的3/4那么大,人口只有50万,却拥有世界已知石油储量的1/5。
该句为简单句,主语为Kuwait,谓语possesses, 宾语about one-fifth of all the known petroleum reserves in the world。
for instance为插入语,举例说明;which isa small nation at the head of the Persian Gulf是一个由which 引导的非限定性定语从句,修饰先行词Kuwait;介词短语with an area only three-fourths that of Massachusetts and a population of about half a million做后置定语同样修饰Kuwait 一词。
参考译文课文A石油1油,和煤一样,存在于沉积岩中,而且可能由死去很长时间的生物有机体形成。
含有石油的岩石几乎都来源于海洋,所以形成石油的有机物一定是海洋生物,而不是树木。
2 石油,并不是来自于逐渐积聚的木质物质,而可能是来自于逐渐积聚的海洋生物的脂肪物质。
比如浮游生物:大量浮游在海水表层的单细胞生物。
3 有机物的脂肪物质主要由碳氢原子组成,因此并不需要太多的化学变化就可以形成石油。
生物有机体只需在缺氧的条件下沉积到海湾浅水处的淤泥里。
其脂肪不是分解腐烂,而是逐渐积聚,并在深层的淤泥里圈闭起来,进而经过细微的原子重组,最终形成石油。
4 油比水轻,呈液态,会经由上方覆盖的孔隙性岩石向上渗透,在地球上有些地区到达表层,古人将这些表层石油称为沥青、柏油或异庚烷。
在古代和中世纪,这些石油油苗常被看作药品而不是燃料。
5 当然,表层的油苗数量很少。
而石油油藏上方有时覆盖的是非孔隙性岩石。
石油向上渗透抵达该岩石,然后在岩石下方逐渐积聚形成油层。
若在上方的岩石上钻个孔,石油就可以通过该孔向上迁移。
有时压力过大,石油会向高空喷出。
1859年在宾夕法尼亚州,由埃德温·德雷克成功打出第一口井。
6 如果可以发现一个合适的地点(勘探人员已经识别出地下可能圈闭有石油的地层结构),那么就很容易抽取这一液体燃料,这要比派人到地下把大块的固体煤炭砍成小块要容易得多。
而且一旦获得石油,可以通过地上管道运输,而不必像煤一样,由运货车经过繁重的装卸任务来运输。
7 石油便于抽取,易于运输,促进了石油的应用。
石油可以蒸馏成不同的馏分,每种馏分均由特定大小的分子组成,分子越小,该馏分就越容易蒸发。
8 到19世纪下半叶,最重要的石油馏分是由中等大小的分子构成的煤油,它不易蒸发,被用于照明。
9 然而,到19世纪末人们研制出了内燃机。
内燃机是通过在汽缸里将空气与可燃气体混合,产生爆炸来提供动力的。
最便利的可燃气体是汽油——石油的又一馏分,由小分子构成,容易蒸发。
10 这种内燃机与蒸汽机相比,机身小巧,可以瞬间启动;而蒸汽机需要一定时间,等待储水加热到沸点。
11 随着各种带有内燃机的汽车、卡车、公共汽车、飞机等交通工具的使用,对于石油的需求激增。
房屋不再用煤,而用燃烧燃料供热;轮船开始使用石油;电力也由燃油提供的能量来供给。
12 在1900年,来自石油的能量只是煤的4%,二战后,由石油的各种不同馏分提供的能量已经超过煤所供给的能量,而现在石油成为推动世界科技发展的主要燃料。
13 石油相对于煤的便利却被另一个事实所抵消:地球上石油的数量比煤少得多。
(这不足为奇,因为地球上形成石油的脂肪物质,要比形成煤的木质物质少得多。
)14 还有另一种复杂情况,即石油的分布不如煤的分布均匀。
世界上的主要能源消耗国有足够的煤,却严重缺乏石油。
美国有世界石油总储量的10%,数十年来一直是主要石油生产国。
现在亦是如此,但是美国大量消耗石油产品,使之成为石油进口国,对于这一重要资源不得不日益依赖其他国家。
俄罗斯石油储量和美国相近,但消耗的少,因而可以成为石油出口国。
15 地球上已知的石油储备约有3/5集中在阿拉伯国家。
例如,位于波斯湾岬角处的科威特,面积只有麻省那么大,人口只有50万,却拥有世界已知石油储量的1/5。
16 由石油引发的政治问题已经变得至关重要。
Text BThe Future of Alternative EnergySentence structure analysis1. The cheaper rate is still more expensive than the average national price of electricity,which in 2003 was a little over 8 cents per kilowatt-hour, according to the U.S.Department of Energy’s Annual Energy Review.(Para. 9) 即使略微便宜的光电价格仍然高于全国电价的平均价格,据美国能源部发行的《能源周刊》统计,2003年每千瓦时的电价均价略高于8美分。
该句包含一个比较状语从句和一个非限定性定语从句,介词短语according to…做状语表示补充说明。
2. Other recent advances include thin film photovoltaic technology, a high-tech coatingthat converts any surface covered with the film into a solar-electric power source.Boats and RVs that use the film are now on the market. (Para. 10) 其他最新的发展包括薄膜光电技术,这种高科技的涂层能够将任何覆盖此类薄膜的表面转化成一种光电电源。