人教版英语必修三

人教版英语必修三Unit4Astronomy:thescienceofthestars 重难点Teaching aims: 1. Enable students to improve their listening skills and reading ability.2. Enable students to understand the development of gravity and how gravity affects us in different times and places.3. Arouse students interest to search for the mystery of space.Emphasis: 1. Words and expressions: gravity, float, cheer up, now that, break out, etc2. Astronomic knowledge like gravity and black hole.Difficulties: 1. Help the students to understand the development of gravity.2. Help the students to know how gravity influences us.Teaching methods: skimming, scanning, discussing.Teaching aids: a tape recorder, a projector and a computer.【词汇识记】1太阳系solar system 2及时，总有一天 in time3阻止，制止prevent from 4依靠，信赖depend on5感到高兴cheer up 6既然，由于now that7蔓延spread 8一般而言generally speaking9坚固的solid 10. 作一次太空旅行make a trip into space11熟悉，掌握get the hang of 12突发，爆发break out13增多，使繁殖multiply 14大气层，气氛atmosphere15消失，经过go by 16与不同be different from17冷却cool down 18失重地weightlessly19全球变暖global warming 20地心引力gravity【单词用法】1、multiply (数目上)增加，增多；乘；（使）繁殖 【经典例句】1) Our problems have multiplied since last year. 2) 2 and 5 multiply to make 10. 3) 6 multiplied by 5 is 30. = Multiply 6 by 5 to make 30.4) The plants here multiply rapidly. 2、encourage 鼓舞；促进；怂恿。后接名词、代词，也可接不定式作宾语补足语。如：High prices for corn and wheat will encourage farming. 玉米和小麦的高价将促进农业的发展。【经典例句】My success encouraged me to continue. 我的成功鼓励我继续干下去。He encouraged me to learn dancing. 他鼓励我去学跳舞。3、development (1)U成长,发育；发展(过程)；扩展【经典例句】The development of this industry will take several years. 这项工业的发展要经过几年的时间。 (2)C开发区, 新社区 a new housing development 新建住宅区(3) C进化,进展；新情况,新闻What are the latest developments?【经典例句】The use of computers in teaching is a recent development.教学上使用计算机是新近才有的事.4、atmosphere tm sfI n.大气层；气氛atmo-(空气,蒸汽) + sphere(球,球体)，大气层是个充满空气的球体。【经典例句】The exciting atmosphere of the football match held my breath.足球比赛的紧张气氛让我大气不敢出。1）同根词：hemisphere (hemi-半) 半球体、半个球;（地球或天体的）半球。如：The Northern Hemisphere is the part of the world north of the equator,and the Southern Hemisphere is south of the equator.北半球是地球赤道以北的部分，南半球是赤道以南的部分。2）该词可引申为“气氛”，即对某一环境的感受。如： In a bar or a cafe,usually there is a very cozy atmosphere.在酒吧或咖啡厅里，往往都有一种非常温馨的气氛。Better late than never. 迟做总比不做好；晚来总比不来强。5、violent vaI l nt adj.猛烈的；激烈的；强暴的vi-（力量）+ olent（香味的,有气味的）violent(猛烈的)，香味很浓烈。【经典例句】 The boat sank in a violent storm at sea.船在海上强烈的风暴中沉没。1）其基本词义：显示巨大力量的，以巨大力量行动的，或由巨大力量产生的，如：a violent attack猛烈的进攻2）由其基本词义引申至“具有或表现为巨大感情的力量的”，如：violent dislike极其的厌恶3）该词常常可以修饰一些极端的词，如：violent pain极度痛苦；a violent death横死、暴死4）该词的名词形式为violence，副词是violently。6、solid s lId adj. 固体的；坚固的n.固体；立体so+ lid (盖子)，“盖子”都是“固体的”。【经典例句】 He is a man with good solid flesh on him.他是一个肌肉结实的人。1）注意物质的三种形态：固体、液体、气体，分别是solid，liquid，gas。solid，liquid既可以作形容词，也可以作名词，gas不能作形容词。2）solid还可以指“质密的、紧密的、结实的”。如：The new office building is a very solid construction.新建的写字楼非常坚固。该词还可引申为“可靠的”。如：solid facts可靠的事实。另一个用法也必须掌握，solid还可以意为“相当可观的”，如：a solid meal丰盛的饭菜。7、explode Ikspl d vi.& vt.(使)爆炸；爆发ex(由出来)+p+lode（复成矿），随便“挖”（ex-）“矿”（lode）容易引起“爆炸”。【经典例句】 The boiler exploded and a big fire ensued.锅炉爆炸了,随着而来的就是一场大火。1）同义词或词组：blow up意为“爆炸、炸毁 ”，如：blow up the bridge把桥炸毁;burst意为“爆裂、爆发（尤指含有液体的东西）”；erupt意为“（尤指火山）爆发、剧烈活动”。2）explode也可以作及物动词。如：The children exploded three firecrackers.孩子们燃放了三个爆竹。3）作不及物动词表示“带着声响粉碎”。如：I threw the vase on the floor and it exploded into tiny pieces.我把花瓶扔到了地板上，花瓶砰地一声摔个粉碎。4)表示“突发、发作”，常常含有剧烈的意味。如：My neighbor exploded in rage at the trespassers.我的邻居对闯入者勃然大怒。8、planet pl nIt n.行星plan (计划)et 【经典例句】 It is said that a tenth planet has been discovered by American scientists.据说美国科学家又发现了第十颗行星。1）各种星星的英文称呼：star恒星,planet行星,satellite卫星,comet彗星,meteoroid流星体。2）planet等虽是天体，但宇宙中不止一个planet，所以前面不一定要用定冠词。如：The earth is a planet.地球是一个行星。9、harmful h mf l adj. 有害的;伤害的harm（伤害）+-ful（形容词后缀）【经典例句】 Smoking can be harmful to your health.工员吸烟对身体有害。1）反义词：harmless意为“无害的”；介词搭配常用to，如：be harmful to。2）名词形式harm及由其构成的短语有：do no harm无害；do sb.harm=对有害；do sth.harm 对有害；do harm to sb.对有害；do harm to sth.对有害;mean no harm没有恶意；harm也可以用作动词，表示损害;对有害处。如：I have never harmed anybody.我从未伤害过任何人。10、spread spred vi.&vt.伸展；展开；传播sp+read(读；有学问的)【经典例句】 The fire spread from the factory to the houses nearby.火从工厂蔓延到附近的房舍。1）近义词：unfold意为“打开,显露,开展”；extend意为“扩充,延伸,伸展”。2）spread既可以是及物动词也可以作不及物动词。如：The bird spread its wings.这只鸟张开了翅膀。（及物动词）spread也可以是名词。如：The birds wings have a spread of three feet.那鸟的双翅展开有3英尺长。spread常跟out搭配使用。如：We spread the bicycle parts out on the floor.我们将自行车零件摊开。11、method me d n. 方法meth(兴奋剂)+od(自然力)【经典例句】 Our teacher is showing us a new method of writing.老师告诉我们一种书写的新方法。1）近义词：mode意为“方式,模式”；manner意为“方式,样式,习惯”;way意为“方式，方法”。2）method和mode,manner,way 的区别： method可以指做某件事的具体步骤或程序，也可以指抽象概念“条理”。mode 虽然有时能与 method 互换使用，但在用 mode 的地方应当是由传统或习俗形成的方式方法，或因人而异的个人喜欢采用的方法或方式。 manner 主要表示个人喜欢采用的方式，与 mode 的这层含义很近，但mode 是个正式词汇，而且 manner 不用于表示传统或习俗所形成的方式方法。way 是个最通用最不正式的词，可以用来代替前面的任何一个词。 Every profession produces its own best.行行出状元。 12、prevent prIventv. 防止；预防pre-(在之前)+vent （出口），把东西放在“出口”之前就 “阻止”了。【经典例句】 It is the job of the police to prevent crime.防止犯罪是警察的职责。1）同义词（组）：stop意为“阻止”；keep from意为“阻止”；反义词：permit意为“允许”。 2）prevent常与from搭配使用。如：What prevented you from joining us last night?昨天晚上什么事使你不能参加我们的晚会?上一例句中prevented可换成stopped或kept。如用prevented或stopped，from均可省略，但是用kept则不能省略。13、depend dIpend vi.依靠；依赖de(剥夺,分离)+pend(悬而未决)不再“悬而未决”，就有了“依靠”。【经典例句】 Health depends on good food,fresh air and enough sleep.健康依靠的是良好的食物、新鲜的空气和充足的睡眠。1）同义词：rely意为“依靠，依赖”。2）depend还可表示“信任，信赖”。如：Can I depend on you?我可以信任你吗？表示“视情况而定”也是该词常用之意。如：It all depends on how you deal with the problem.那要看你如何应付这问题而定。【短语讲解】1.cheer up : 欢呼，喝彩，感到高兴，使高兴。当看到球队的到来，人群欢呼起来。cheer up when they saw the team arrive.他带她去听音乐会来使她高兴。He took her to the concert to cheer her up .2.now that :既然，由于既然每个人都到了，我们就可以开始会议。Now that everybody is here , we can begin the meeting.由于你是一个大男孩,你就必须行为表现得更好. Now that you are a big boy , you must behave better.3.going round the sun为现在分词短语，做定语，表示一般的动作。例如：Men breaking the law will be punished.Men who break the law will be punished. 现在分词短语作定语，也可表示进行的动作。例如：Can you see the girl dancing with your boyfriend?Can you see the girl who is dancing with her boyfriend? 你能看到与男友跳舞的那个姑娘吗？4.Its generally believed that一般认为 generally speaking 一般而言，概括来说 1) Its generally believed that girls work harder than boys do. 2) Generally speaking, women cry more easily than men. 5.depend on sb. / sth. sb. to do sth. sb. doing sth.sb. /sth. for sth. 相信，信赖, 依靠,依赖, 视而定，取决于 1) When you are in a strange place youd better depend on the map. 2) You cant depend on others to help you. 3) All living things depend on the sun for their growth. 4) He depends on his pen for his living. 5、in timein(在里）+time（时间）Will you be home in time to watch the interesting TV program?你到家赶得上看那个有趣的电视节目吗？1）注意in time和on time的区别：in time指“及时，在时限到来之前”；on time则指“准时，按时间表”。2）in time还可表示“最终，在不定时间内”。6、cool down 凉快起来；渐渐冷却cool(凉爽)+down(下来)凉爽下来,渐渐冷却Dont cover the TV set until it cools down.等电视机凉下来再盖上。1）同义词组：cool off变凉、平静下来2）cool down还可用于人的心境，指“平静下来；使平静下来”。如：She didnt cool down for hours after that argument.争吵过后，她好几个小时都没有平静下来。7、because of 因为because(因为）+of(的）I went back not because of the rain,but because I was tired.我回去不是因为下雨，而是因为我累了。1）同义词组：due to(由于，应归于)；owing to(因为，由于)；thanks to(多亏),as a result of（由于而产生）。2）与because 的区别：because是连词，后面接句子；because of 是介词短语，后面跟名词或名词性短语或代词。8、as well as也,又 as(同样地）+well(好）+as(和一样)The young man is courageous as well as strong.那个年轻人既健壮又勇敢。1）as well与too用法相似。如：Im going to London and my sisters coming as well.=Im going to London and my sisters coming too.我要到伦敦去，我妹妹也要去。2）as well as也可表示同级比较。如：Now she can speak English as well as a native speaker.现在她的英语和英语国家的人说得一样好。3)和not only.but also.进行比较：as well as 强调as well as 前面的部分；而not only.but also.强调 but also.中的内容。9、for the first time第一次；首次for(为）+the first(第一）+time(次）【经典例句】 When school began last summer ,most of us met for the first time去年夏天开学时，我们大都是第一次见面。head of ones time比所处时代先进10、all over 到处；浑身all(所有）+over(遍及）【经典例句】 The cloth is embroidered all over with roses.这块布绣满玫瑰花。1）表示全世界，还可用以下方式：around the world,throughout the world等。2）all over还可用作副词短语，表示“到处、四处”。如：She looked all over for the lost book.她到处找那本丢了的书。11、go by 消失；经过go(走）+by(经过）【经典例句】 As time goes by,everything will be OK. 随着时间的推移，一切都会好起来的。1）go by可用于时间，也可用于地点。如：A car went by.一辆小车开过去了。2）go by的其他用法：依照，凭判断。如：You cant go by what the children say.你不能照孩子们说的去做。3)go by还有“短期访问，拜访”之意。如：My parents were away when we went by last week.上周去看望我的父母，他们不在家。12、break out 突发；爆发break意为“断裂”，物体断裂时的响声“咔嚓”一声爆出来了，即为“突发、爆发”。【经典例句】 It was almost midnight that a fire broke out in the neighborhood. 昨天快半夜了这附近发生了火灾。1）break out的名词形式为outbreak。如：The outbreak of SARS cost many peoples lives that year.那年爆发的SARS夺去了很多人的生命。2）break out可指大火、战争等突然爆发。如：World War broke out in 1939.第二次世界大战是1939年爆发的。3)break out还可指突然发出某种声音。如：She broke out in curses in her dream.她在梦中大声咒骂起来。【重要句子解析】1. What it was to become was uncertain until Notuntil直到才It is/was not until that 强调句He didnt leave school until seven oclock. 他昨天直到七点才离开学校.It was not until seven oclock that he left school 他们到了中国才能看了长城.（It was not until they came to China that they could see the Great Wall.）2. The earth became so violent that it was not clear whether the shape would last or not. 1) violent 猛烈的，激烈的 violence n. 暴力 2) last v. 持续 The fine weather only lasted for a few day. 好天气只会持续几天 Friendship lasts forever. 友谊长存3. They were in time to produce carbon, which were to make important is in time: sooner or later; eventually 迟早;最终 Ill see him in time. 我迟早会遇见他. in time (for sth. /to do sth.): not late及时；不迟She will be back in time to prepare dinner. 她会及时回来准备晚餐.Do you think we can get there_in time for the train?你认为我们能及时赶上火车吗?与time相关的短语: on time 按时;准时 In no time 立刻,马上 at times 有时 at a time 每次;依次 once upon a time 从前 at one time 从前 for the time being 暂时 from time to time 不时地(sth) be to (do): 1. 不可避免要发生或必须发生。 They said goodbye, little knowing that they were never to meet again. She is to be honoured for this great work. 2 表示按计划、安排要发生的动作When are they to hand in their plan？3 表命令Tell her she is not to be back late!与will do, be about to, be going to do 区别:1) Will do/shall do 多指客观上将要发生的动作,句中通常有一个表将来的时间状语. The sports meeting will be held next Saturday.2) Be about to do 表即将正要做某事,句中不加时间状语,但可以和when连用. I am about to leave.3) Be going to do 表事先经过考虑打算去做或有明显迹象可能发生的事 It looks as if it is going to rain4. It was not immediately obvious that water was to be fundamental to the development of life.1) It was (not ) obvious that显而易见的2) Be fundamental to 对于来说是必要的4.This produced a chain reaction, which made it possible for life to develop.1) Chain reaction 连锁反应2) Make it possible for life to develop. 使生命的发展成为可能 make it + adj./n. sb. /sth. to do sth.The group leader make it possible for us to work together. 组长让我们可以一起合作.The teacher made it easy for them to understand the question. 老师让他们跟容易地明白那个问题.5. allowed the earth to dissolve harmful gases1) Allow to = permit to do2) Harmful adj. Opp: harmless harm n.be harmful to sb./sth.= do harm to sb. /sth. 对有害Too much carbon dioxide is harmful to / does harm to the environment. 过多的二氧化碳对环境有害.6.They multiplied and filled the oceans and seas with oxygen, which encouraged the 1) Multiply v. 乘: 增加Four multiplied by seven is twenty-eight. 7.乘以4等于28.Our homework have multiplied since we came to high school. 我们的功课自上以来增多了.Mosquitoes multiply rapidly in summer. 蚊子在夏天繁殖得很快.2) encourage v. 鼓励The teacher encourages us to speak English in class. 老师鼓励我们上课说英语.7. Later when the plants grew for the first time. For the first/second/third time 第一/二/三次 在句子中作时间状语I saw her for the first time. 我那是第一次见到她.Ten years later, he came here for the third time. 十年后,他第三次来到这里.与the first time 区别:he first time 后可以跟句子,引导时间状语.That is the first time that I have seen him. 这是我第一次见到他.I loved him the first time I saw him. 第一次见到他,我就爱上了他.9. The laid eggs too and existed on the earth exist in 存在与之中 exist on 靠为生 exist by 靠生存It was impossible for them to exist on_such a small income. The universe exists in space. The wild man existed by hunting wild animal in the forest.10.because the gave birth to young babygive birth to 生小孩She gave birth to a fine healthy girl. 她生了一个健康漂亮的女孩.有关 birth的短语:By birth 天生地,生来He is French by birth.a second birth= rebirth 重生, 再生God gave him a second birth.11. spread all over the earth. 在全地球蔓延开来Spread v. 扩大，传布The bird flu is spreading in that city. 禽流感正在那个城市里蔓延We spread butter on bread. 我们把奶油涂到面包上。 12. Thus they have, in their turn.1) Thus adv. 因此；从而She studied hard, thus she got high marks.He forgot to turn on the radio and thus missed the program 2) In ones turn 轮到某人It will be in Sams turn to be on duty tomorrow.13.which prevents heat from escaping fromprevent sth./ sb. (from) sth./doing sth.阻止某人某物做某事同义词组：stop (from)keepfrom（此处from不能省）We are prevented/kept/stopped from having breakfast in the classroom. 我们被阻止在课室吃早餐14.millions of years to come will depend on whether depend on sb. 依靠,相信某人depend on sth. 取决与某物Well all depend on you to make a decision. 我们都靠你来做决定了Whether to hold the sports meeting or not will depends on the weather . 明天是否能开校运会取决与天气15.When we get closer to the moon, we shall feel its gravity pulling us but it will not be as strong a pull as the earths. 当我们更接近月球时，就会感到月球的引力在拉我们。但是，月球的引力不像地球的引力那么大。get close to 靠近，接近，指动态变化be close to 距.近，指状态The school is close to the post office.与get相关的短语:get along 相处融洽，进展等get down to 开始认真对待，开始认真考虑get on 上车get through 到达；通过；办完，花光(钱、时间等)。get to 到达16. “walking does need a bit of practice now that gravity has changed.”.既然引力改变了，走路也的确需要练一练了。 now that同since相似，语气较弱，强调人们已知的事实。Translation:1. 既然你忙, 就让我给你做吧。Now that you are busy, let me do it for you.2. 既然人都齐了, 咱们开始干吧。Now that everyone is here lets start work17.We watched, amazed as fire broke out on the outside of the spaceship as the earths gravity increased.break out 它与happen, take place, come out等词的用法一样，是不及物动词，不能带宾语，不能用于被动语态。1) 战争爆发The American Civil War broke out in 1861. 美国内战爆发于1861年。 2) 发生争吵A quarrel broke out between them. 他们之间发生了争吵。3) (火灾)发生 Afirebrokeoutinhishouselast night. 昨晚他家里失火了。与break相关的短语: break down 打破; 毁掉; 破除; 坍塌; 坏掉 break in 破门而入; 打断break away from 脱离政党; 打破陈规 break through 突围; 突破; 冲垮; 克服break up 打碎; 拆散; 分裂; 分解break ones word/promise食言; 说话不算数18.The problem was that the earth became violent because it was not clear whether the solid shape was to last or not.问题是地球开始变得激烈动荡，不知道这个固体形状是否会继续下去。n. 固体 solid, liquid, gas adj. 固体的；实心的,无空隙的；结实的，坚固的 solid fuels solid food a solid sphere solid furniturea man of solid build1) Matter has three states: solid, liquid and gas. 2) When water freezes, it becomes solid and we call it ice. be to (do): (something) will definitely happen, or it must happen 不可避免要发生或必须发生 e.g.They said goodbye, little knowing that they were never to meet again.She is to be honoured for this great work.Mr. Clark said to his daughter, “You are to be home by 10 oclock at the latest.” 19.As the earth cooled down, water began to appear on its surface. 随着地球的冷却, 地球的表面就开始出现了水。cool adj.凉快；冷静；冷淡 v. （使）变冷；冷静下来 1) Lets sit in the shade and get cool. 2) I knew I had to keep cool. 3) His play received a cool response from the public. 4) The rain has cooled the air. 5) Let your soup cool a little before you drink it. 6) A heated argument can be settled better if both sides cool down first. 7) I tried to cool her down but she was still very angry when she left. 20.Nobody knew that it was going to be different from other planets going round the sun. be very / much / quite / entirely / totally different from与不同 ）城市生活和农村生活很不同。City life is quite different from country life. 2）他们的品位和我不同。Their tastes are different from mine. There are differences betweenand 与之间有不同之处tellfrom 把与区分开来the same as 与一样be similar to 与相似 【语法解析】一、做主语用的名词性从句，因其在复合句中做主语，又称主语从句，引导主语从句的有从属连词that, whether， 连接代词who, what, which， 连接副词when, where, how, why等。1.连接词：1）从属连词：that， whether等.that 引导主语从句只起引导作用，本身无实际意义，在主语从句中不充当任何成分，但不能省略。 That she left him cut him to the heart.That he will come is certain.由whether及其他连词引导的主语从句放在句首，句后都可。 Whether it will please them is not easy to say.Whether shes coming or not doesnt matter too much.2)连接代词who ，what ，which, whatever, whichever, whoever What seems easy to some people seems difficult to others.Which side will win is not clear.3)连接副词when，where， how， why等。Why he did it remains a mystery.When they will start is not known yet.How he became a great scientist is known to us all.2.位置： 主语从句可以前置，也可以后置。用it做形式主语，而把主语从句放在句末，常用下面几种句型。1）It + be + 表语 +主语从句表语：（名词， 形容词，过去分词）It is a pity that we cant go.It is no surprise that our team should have won the game.It is an honour that I was invited to attend the meeting.2）It+不及物动词或短语+主语从句It seemed (happened, doesnt matter, has turned out) that It happens that they were absent.It seems that Alice is not coming to the party at all.It doesnt matter whether she will come or not.It makes no difference where we shall have the meeting.3) It +及物动词（被动语态）+主语从句It has been decided that the exhibition will not open on Sundays.注意:1）主语从句在句首时，必须由连接词引导，不能省略这些连接词；但是如果用it做形式主语，而把主语从句放在句末时，从属连词that可以省略。误：They should like each other is natural.正：That they should like each other is natural.正：It is natural that they should like each other.2)如果主语从句放在句首，不能用if引导，但是如果用it 做形式主语，而把主语从句放在句末时，也可以用if引导.误：If Mary really heard him is really doubtful.正：It was doubtful if Mary really heard him.二、英语倍数表达法1.用times表示倍数（一般限于包括基数在内三倍或三倍以上的数。表示两倍的数，一般用twice）其句型有：1）.times+形容词（副词）比较级+than.。如：This hall is five times bigger than our classroom.这个大厅比我们的教室大五倍。（是我们教室的六倍大）2）.times +as+形容词（或much）或副词原级+as.。如：The big box is four times as heavy as the small one.大箱子是小箱子的四倍重。3）.times +the+名词（size,height,weight,length,width）+of。如：This big tree is four times the height of that small one.这棵大树的高度是那棵小树的四倍。（比那棵小树高三倍）4）.times+more+名词（可数，不可数）+than.。如：There are four times more books in our library than in yours.我们图书馆藏书（数量）是你们图书馆的四倍。（多三倍）5）.times +as many（或much）+名词+其他。如：There are three times as many apples in this basket as in that one.这个篮里的苹果是那个篮里的三倍。There are five times as many students as we expected.这里的学生是我们预计的五倍。6）.times +over+被比对象，表示“增加倍”。如：The grain output in that village was twice over that of 1978.那个村的粮食产量比1978年的增加了两倍。7）.times +that of+被比较的对象表示“是倍”。如：In this workshop,the output of July was 3.5 times that of January.这个车间7月份的产量是1月份的3.5倍。2.用double表示倍数。1）double作形容词，表示“两倍的”。如：The production is now double what it was ten years ago.现在的产量是十年前的两倍。2）double作动词，意为“是的两倍”。如：The output has been