1、Section Grammar情态动词语法图解典句感知The topic of the poem cant be travel.It must be something more personal.It may be friendship.It might be the journey through life.Li Bai must have had a strange life.He cant have been interested in a normal life.He may have died when he fell out of a boat.You should read t
2、he poem sometime.Could you answer a few questions, please?I told her to stop singing, but she wouldnt listen.语法领悟(1)句表示推测，其中句表示对过去所发生的事情的推测。(2)句表示说话人的意愿，意为“应该”，句表示请求， 句表示意愿。一、must的用法1在肯定句中，must可以表示肯定推测，意为“一定，肯定”，其中否定形式为cant。The light in her room is still on; she must be at home now.她房间的灯还亮着，她现在肯定在家。
3、She cant be at home. I saw her leave home ten minutes ago.她不可能在家，10分钟前我看见她离开家了。He must be sleeping now.现在他肯定在睡觉。2表示义务、命令等，意为“必须”，语气比should强烈。其否定形式为mustnt (不准，禁止)。You must finish your homework this afternoon.今天下午你必须完成你的家庭作业。You mustnt smoke here.你不准在这儿吸烟。3对以must开头的一般疑问句进行肯定回答时用must，进行否定回答时用neednt/don
4、t have to(不必，没必要)。Must we finish the work today?我们今天必须完成这项工作吗？Yes, you must./No, you neednt/dont have to.是的，你们必须完成。/不，你们不必。4表示与说话人的愿望相反或不耐烦，意为“偏要，偏偏”。After I gave her my advice, she must go and do the opposite.我给她出了主意后她偏反着干。Why must you always interrupt me?你为什么非要一直打断我呢？归纳拓展 must have done 意为“一定做了”，用
5、于肯定句中，表示对过去的情况进行比较肯定的推测。I didnt hear the phone ring. I must have been asleep.我没听见电话响，我一定是睡着了。即学即练1 单项选择1You _ be Carol. You havent changed a bit after all these years.AmustBcanCwillDshall答案：A解析：句意：你一定是卡萝尔。这些年来你一点儿没变。根据第二句可知，此处应用must表示肯定推测，意为“一定，肯定”。2Harry is feeling uncomfortable. He _ too much at t
6、he party last night.Acould drink Bshould drinkCwould have drunkDmust have drunk答案：D解析：句意：哈里感觉不舒服。昨晚的聚会上他肯定喝得太多了。由句意和last night可知，此处表示对过去情况把握较大的肯定推测，故用must have done结构，故选D。二、cant的用法1用于否定句中，意为“不可能”，表示把握比较大的推测。“cant动词原形”表示对现在或将来的事的否定推测；“cantbev.ing”表示对现在发生的事的否定推测；“canthavev.ed”表示对过去的事的否定推测。That cant be
7、 Mary, for she is in hospital.那不可能是玛丽，因为她在住院。He cant be working at this time.这个时候，他不可能在工作。Mr Smith cant have gone to Beijing, for I saw him in the library just now.史密斯先生不可能去北京了，因为我刚才还在图书馆看到他。2表示没有能力做或不能够发生，意为“不会，不能”。I can speak English, but I cant speak French.我会说英语，但是不会说法语。Could you walk a bit more
8、 slowly? I cant follow you.你可以走得稍微慢一点儿吗？我跟不上你。3表示不允许或不同意，意为“不能，不可以”。We cant enter the museum without a ticket.没有门票我们不能进入博物馆。巧学妙记 “一点三法”巧解情态动词表推测题：一点：同一情态动词不同时态下的形式并不表示时间背景的不同，只是强调可能性的大与小或语气的强与弱。三法：1.肯定的推测，肯定句中表推测的情态动词按照可能性从大到小排列的顺序是mustwillwouldought toshouldcancouldmaymight；2否定的推测，否定句中表推测的情态动词按照可能性
9、从大到小排列的顺序是cantcouldntmay notmight not；3疑问句中的推测往往用can或could。即学即练2 单项选择1George _ too far. His coffee is still warm.Amust have goneBmight have goneCcant have goneDneednt have gone答案：C解析：句意：乔治不可能走了很远，因为他的咖啡还是热的呢。根据句意可知，此处用cant have done结构，表示对过去情况的否定推测。故选C。2It _ be the postman at the door. Its only six o
10、clock.AmustntBcantCwontDneednt答案：B解析：句意：门口不可能是邮递员。(现在)才六点钟。由“Its only six oclock”可知，此处表示对现在情况的否定推测，应用cant(不可能)，而mustnt表示“禁止”，wont表示“不会”，neednt表示“不必”，均不符合句意。三、may/might的用法1表示征求同意或许可，意为“可以”(在疑问句中表示“征求同意”，在陈述句中表示“许可”)。表示征求同意时，might比may的语气更委婉。一般疑问句的肯定回答用may/can，但做出否定回答时要用mustnt/cant，表示“禁止/不可以”。You may k
11、eep the book for two weeks.这本书你可以借两个星期。May I watch TV after supper?晚饭后我可以看电视吗？Yes, you may/can./No, you mustnt/cant.是的，你可以。/不，你不准看/不能看。即学即练3 单项选择_ I take the book out?Im afraid not.AWillBMayCMustDNeed答案：B解析：句意：我可以把书带出去吗？恐怕不能。根据选项可知，四个选项中只有May表示征求同意。2表示可能性，意为“可能，也许，大概”。用于肯定句或否定句中，用might比may语气更加不肯定。ma
12、y not/might not表示“可能不”之意。He may be very busy these days.他这些日子可能很忙。Are you coming to Marys birthday party?你参加玛丽的生日聚会吗？Im not sure. I might go to the concert instead.我不确定，相反我可能去听音乐会。即学即练4 1完成句子有时候举例也许有助于解释抽象的概念。Sometimes it_might/may_be_helpful to use examples to explain abstract concepts.解析：本句中it作形式主
13、语，真正的主语为后面的动词不定式短语。情态动词may/might意为“可能，也许”。2单项选择You _ feel all the training a waste of time, but Im a hundred percent sure later youll be grateful you did it.AshouldBneedCshallDmay答案：D解析：句意：你可能认为所有的培训都是浪费时间，但是我百分之百确信以后你将感谢你所做的这一切。根据句子的后半句“but Im a hundred percent sure later youll be grateful you did
14、it”可判断出，前半句表示对所述情况的一种推测，故选D。may意为“也许，可能”。Life is unpredictable; even the poorest _ become the richest.AshallBmustCneedDmight答案：D解析：句意：生活是不可预测的，即使是最贫穷的人也可能成为最有钱的人。might意为“可能”。归纳拓展 (1)表示对现在或将来事情的推测，用“may/might动词原形”。Today is Sunday. She may not be in the office.今天是周日。她可能不在办公室。I think he may/might come
15、tomorrow.我认为明天他可能会来。(2)对已发生事情的推测用“may/mighthave过去分词”，表示“过去可能做过某事”。She hasnt been here by now; she may have missed her train.到现在她还没来，可能是没赶上火车。Some of you may have finished Unit One. If so, you can go on to Unit Two.你们中的一些人可能已经完成了第一单元，如果这样的话，你们可以继续第二单元。即学即练5 单项选择I left my handbag on the train, but luc
16、kily someone gave it to a railway official.How unbelievable to get it back! I mean, someone _ it.Awill have stolenBmight have stolenCshould have stolenDmust have stolen答案：B解析：由语境可知，空处是对已发生的事情进行推测。might have done表示“可能做过某事”。故选B。3may常用于祈使句中，表示祝愿。May you succeed!祝你成功！May all your dreams come true!愿你梦想成真
17、！四、should的用法1表示责任、义务，意为“应该”。She should look after her child well.她应该把孩子照顾好。We should respect our parents.我们应该尊敬我们的父母。2用在虚拟语气中。在表示请求、建议、命令、要求等意义的名词(如request, require/requirement, suggest/suggestion, recommend/recommendation, advise/advice, command, order, insist, ask等)后的主语从句、宾语从句、表语从句和同位语从句中，谓语常用“sho
18、uld动词原形”，should可省略。I suggested (that) Jane (should) start at once.我建议简马上出发。I recommend (that) he (should) see a lawyer.我建议他去找个律师。He gave the advice that we (should) do the work carefully.他建议我们认真做这项工作。Their request is that their wages (should) be increased by 30%.他们的请求是工资涨30%。即学即练6 单句改错Some classmate
19、s suggest we can go to places of interest nearby.删除can或将can改为should解析：此处suggest意为“建议”，其后的宾语从句要用虚拟语气，谓语动词用“should动词原形”，should可以省略。3表示按常理经验进行的推测，意为“应该会”。They should be there now.按理他们现在应该在那儿了。Dinner should be ready now.现在晚饭应该准备好了。4表示惊讶、难以置信或不应该发生的事，意为“竟然”。Why should you come so late today?你今天为什么来得这么晚？T
20、he man should be so rude to a lady.这个男人竟然对女士那么粗鲁。即学即练7 单项选择Its strange that he _ have taken the books without the owners permission.AwouldBshouldCcouldDmight答案：B解析：句意：很奇怪，他竟然未经主人的许可就拿走了那些书。should “竟然”，符合句意。5在条件状语从句中，should表示“万一”。If you should change your mind, do let me know it.万一你改变想法的话，一定要让我知道。归纳拓
21、展 should have done意为“本该做某事(而实际上未做)”，表示责备或惋惜之情，相当于ought to have done; shouldnt have done意为“本不该做某事(而实际上做了)”，相当于oughtnt to have done。Yesterday was the deadline and he should have completed his work.昨天是最后期限，他本该完成工作的。Tom shouldnt have told me your secret, but he meant no harm.汤姆本不该把你的秘密告诉我，但他并无恶意。即学即练8 1
22、单项选择Sorry, Mum! I failed the job interview again.Oh, its too bad. You _ have made full preparations.AmustBcanCwouldDshould答案：D解析：根据语境可知此处应用should have done结构，表示“本应该做某事(而实际上未做)”，暗含对对方的责备之情。2完成句子你不该打断会议来告诉我那件事，你本可以会后告诉我。You shouldnt_have_interrupted/oughtnt_to_have_interrupted the meeting to tell me t
23、hat; you could have come to tell me afterwards.解析：shouldnt have done/oughtnt to have done结构表示“过去本不应该做某事(实际上却做了)”。五、could的用法1表示有能力做或能够发生，意为“能，会”。He couldnt sleep, although he tried to.尽管他想睡，但睡不着。即学即练9 单项选择1It was really annoying; I _ get access to the data bank you had recommended.Awouldnt BcouldntCs
24、houldntDneednt答案：B解析：句意：这真的很让人恼火，我无法使用你推荐的那个数据库。根据句意可知应选couldnt表示“不能够”。wouldnt不愿意；shouldnt不应该；neednt不必。2It was so noisy that we _ hear ourselves speak.AcouldntBshouldntCmustntDneednt答案：A解析：句意：太吵了，我们都没法听到自己说话。情态动词couldnt表示“不能够”，符合句意。shouldnt不应该；mustnt不准；neednt不必。2表示请求允许或帮助，意为“能，可以”。在疑问句中could语气比can更委
25、婉。注意在回答时不可用could，通常用can。Could/Can I use your pen?我可以用一下你的钢笔吗？Of course, you can.当然可以了。Could/Can I go home now?我现在可以回家吗？Yes, you can.是的，你可以。3表示说话人的推测、怀疑、惊异或不确定等，常用于疑问句和否定句中。couldnt用来表示由于特定事实或环境某事肯定不会发生，表示“不可能”，couldnt have done意为“不可能做了某事”，表示对过去情况的否定推测。Could what he said be true?他说的可能是真的吗？I saw her ju
26、st now. She couldnt have gone to Sydney.我刚才看见她了，她不可能去悉尼了。特别提醒 could have done既可表示对过去的推测，还可表示“过去本可以做某事(而实际上未做)”。He could have already arrived in Beijing.他可能已经到了北京。He could have passed the exam, but he was too careless.他本可以通过考试，但是他太粗心了。即学即练10 单项选择1I cant find my purse. I _ it in the supermarket yester
27、day, but Im not sure.Ashould leaveBmust have leftCmight leaveDcould have left答案：D解析：根据本空所在句子的时间状语判断，此处叙述的是过去发生的动作；下文说“我不太肯定”，因此表示不肯定的语气，应用“情态动词could/might/mayhave done”结构，因此选D。2We _ the difficulty together, but why didnt you tell me?Ashould faceBmight faceCcould have facedDmust have faced答案：C解析：句意：我
28、们本可以共同面对困难，可你为什么不告诉我呢？后半句用的是一般过去时，由此可知前半句用could have done结构，表示“过去本可以做某事(而实际上未做)”，故选C。六、would的用法1表示意志、意愿或主观愿望。用于各种人称。She said she would help me do the housework.她说她会帮我做家务。即学即练11 单项选择Days later, my brother called to say he was all right, but _ say where he was.Amustnt BshouldntCwouldntDmightnt答案：C解析：句
29、意：几天后，我弟弟打电话说他一切都好，但不愿意说他在哪儿。wouldnt在此表示“不愿意”。mustnt禁止；shouldnt不应该；mightnt或许不。2表示请求。用于第二人称的疑问句中，would比will语气更加委婉。一般疑问句的肯定回答通常用will。Would you please give me a hand?请帮我一把，好吗？3表示过去的一种习惯、倾向或固有性质等，意为“总是，总会”。My father would have a walk after supper.我父亲(以前)总会晚饭后去散步。辨析比较 would/used to区别1would表示过去的习惯性动作，不表示状
30、态。used to可表示过去的习惯性动作和状态。区别2would所表示的过去习惯性的动作现在依然可能存在。used to所表示的过去经常性或习惯性的动作或状态现在已不复存在。I would go to the library when I was free.(过去)我有空的时候常常去那个图书馆。(现在有可能还去)People used to believe that the earth was flat.过去，人们总认为地球是平的。(现在已不再这样认为)Father used not to be so forgetful.父亲过去没这么健忘。(现在很健忘)选择填空1must, can, may
31、, might(包含其否定形式)I havent decided where Im going for my holiday. I may/might go to Australia.Youve been working all day. You must be very tired.Im hungry. I can eat two bowls of rice now.Passengers mustnt talk to the driver while the bus is moving, because it will take his focus off the road.She look
32、s very happy. She must have passed the exam.I guess so. Its not difficult after all.What are you doing, John? Why stop?To be on the safe side, we should fill up the tank now for we may/might run out of gas on the way.You cant be tiredyouve only been working for ten minutes.2should, could, would(包含其否
33、定形式)He was so busy studying and meeting new people that he didnt write to his family as often as he should have, which made him feel regretful.You couldnt have seen her in her office last Friday; shes been out of town for two weeks.Its required that students should go to school on time.When I was yo
34、ung, my mother would read me stories at night.My book, The House of Hades, is missing. Who could have taken it?I shouldnt have watched that movieit gave me horrible dreams.Martin was sick with a high fever; as a result, he could neither eat nor sleep.The price on this packet is wrong. It should be $2.50, not $3.50.It was sad to me that they, so poor themselves, should bring me food.The school took the students proposal into consideration that a party should be held to celebrate the victory.