情态动词(教师).doc

情 态 动 词编写人：何春霞一、情态动词的语法特征1.情态动词不能表示正在发生或已经发生的事情，只表示期待或估计某事的发生。2.情态动词 除ought 和have 外，后面只能接不带to 的不定式。3.情态动词没有人称、数的变化，即情态动词第三人称单数不加-s。4.情态动词没有非谓语形式，即没有不定式，分词等形式。二.情态动词的基本用法(1)can、be able to 和couldcan和be able to都表示能力，意思上没多大区别。但can只有现在和过去时，而be able to有更多的形式。但当成功地完成某一具体动作时，通常不用could而用was/were able to表示。这时was/were able to 相当于managed to，表示经过一番努力，终于能够完成某事。如：Can you use chopsticks? The wounded man was able to get to the village and was saved in the end.can和could：can和could都可以表示能力、技能、许可、建议、请求和(客观的理论的)可能性。但比较委婉客气地提出问题或陈述看法，一般用could，回答时则用can。如：Could you help me carry the bag? Can I help you? Accidents can happen on such rainy days. 注意：位于助动词或情态动词后，只能用be able to .I havent been able to read that report yet. I ought to be able to live on my salary.(2)may/might may/might表示可能，但may比might可能性大。如：Peter may come with us tonight, but he isnt sure yet. (实际的可能性)Why isnt he in class? He may be sick.(生病的可能性较大) / He might be sick.(生病的可能性较小)may/might表示允许或请求；表示没有把握的推测；may用于现在时或将来时，might常用在间接引语中表过去时，但might也可用于现在时间，表示比较委婉的语气，回答用may。如：He says we may leave. He said we might leave.may / might 表示建议或请求，但might比may更客气，无过去时态的含义。May / Might I use your bike? Yes, you can / may. / No, you mustnt注意：（a）might 表示推测时，不表示时态。只是可能性比may 小。He might be at home. （b）may 放在句首，表示祝愿。May God bless you!愿上帝保佑你！（c）may/might as well，后面接不带to 的不定式，意为“不妨，还是好”。You may(just) as well tell me the truth.你还是对我说实话好。(d) may well + do, 表示“很可能,完全能”。 He may well be proud of his son. 他大可为他的儿子感到骄傲。Her appearance has changed so much that you may well not recognize her. 她的模样变化太大，你很可能认不出她了。(3）must must表示必须，应该，没有时态变化。如： You must do everything as I do.must表示肯定的推测。如：The light is still on, so he must be at home.mustnt 表示禁止做某事。如： You mustnt smoke in the office.must可表“偏偏/偏要/非要”，常用于表示与说话人愿望相反及不耐烦的语气。Must you make so much noise in such an hour? 你一定要在这个时候弄出这么大的响声吗？ (4)have to have to 表示“必须、不得不”，是由于某种外界（客观）原因而“必须”，“不得不”做某事，也可表示经常的或习惯性的事“必须”做。have to可用于多种时态中。如：You will have to clean your own boots when you join the army. I have to be at my office every evening.在否定结构中：dont have to 表示“不必”；mustnt表示“禁止”。You dont have to tell him about it.你不必把此事告诉他。You mustnt tell him about it.你不得把这件事告诉他。（5）should / ought toshould和ought to“应当、应该”，表责任或义务。前者比后者语气轻。如：You should / ought to work hard.should / ought to的否定形式表示“禁止”。如： Children shouldnt smoke.should可表示陈述意见，推出建议或请求；而ought to可以表示劝告之意。如：You ought to respect your parents. He suggested that they should leave at once.should意为“竟然”， 表说话人的惊奇、愤怒、失望等。 Why should you be so late today?should用于表推测，意为“估计，想必一定，照说应该”。 The dinner should be prepared bdfore twelve. （6）shallshall用于第二、三人称，表示说话人的意愿，意为“命令”、“警告、威胁、强制”和“允许”等。We shall do as our teacher says. You shall have the book as soon as I finish it.在疑问句中，shall用于征求对方的意见或请求指示，常用于第一、第三人称。如：Where shall he wait for us? Shall we go out for a walk?用于官方文件、法律条文、规定中，意为“应；必须”。It has been announced that candidates shall remain in their seats until all the papers have been collected.（7）will / wouldwill 用于各种人称表示“意志”、“意愿”或“决心”等，否定式wont + 动词。如：I will tell you all about it. Tom wont do such a thing.will用于疑问句中，常用在第二称时表示说话人向对方提出“请求”或“询问”如：Will you please tell her the news when you see her?will 表示习惯性的动作，有“总是”、“惯于”的含义。与第二，三人称连用，表示一种必然性。如：Fish will die out of water. Every morning he will have a walk along this river.would 表示客气的请求、建议或意愿。如：Would you please be quiet? Would you like coffee?would 表示过去反复发生的动作。比used to正式，并没有“现已无此习惯”的含义。如：When I passed my school I would see my teachers who taught me 5 years ago.表示料想或猜想。It would be about ten when he left home.他离开家时应该是10点左右。I thought he would have told you about it.我以为他会告诉你这件事。（8）need need 作“必要”讲，既可作情态动词，也可作实义动词。作实义动词时后面的动词不定式要带to，其变化与一般动词相同。用作情态动词时，多用于否定句及疑问句，没时态和人称变化。如：I need to think it over. Need you go now? Yes, I must./No, I neednt （9）dare dare表示“敢”的意思。作为情态动词时，主要用在疑问句和否定句和条件句中，可有过去式dared. dare若作实义动词，后面可带to的不定式，此时to也可以省略。dare与need的用法相似。如：How dare you say that? She doesnt dare (to) ask her father.（10）used to used to表示过去常常发生的动作或存在的习惯，但现在已不复存在了。如：He used to smoke.三、情态动词表示推测或判断的用法一）can，could，may，might，must 皆可表示推测，其用法如下：1)情态动词+动词原形表示对现在或将来的情况的推测，此时动词通常为系动词。I dont know where she is; she may be in Wuhan.我不知道她在哪儿，她可能在武汉。2)情态动词+动词现在进行式表示对现在或将来正在进行的情况进行推测。At this moment，our teacher must be correcting our exam papers.这时，我们老师想必在批改试卷。3)情态动词+动词完成式表示对过去情况的推测。We would have finished this work by the end of next December. 我们很可能已完成这项工作The road is wet.It must have rained last night.地是湿的，昨天晚上一定下雨了。4)情态动词+动词的现在完成进行式表示对过去正在发生事情的推测。Your mother must have been looking for you. 你妈妈一定一直在找你。5)推测的否定形式，疑问形式用cant，couldnt表示。Mike cant have found his car，for he came to work by bus this morning.迈克一定还没有找回他的车，因为早上他是坐公共汽车来上班的。注意：could，might表示推测时不表示时态，其推测的程度不如can，may。如：It must have rained last night. They should be there right now.She may not be at home. = It is possible that she is not at home.She cant be at home. = It is impossible that she is at home.二）情态动词+have+过去分词must have done 表示过去一定做了，语气十分肯定cant have done 表示过去不可能做了，语气也比较肯定(是上面的否定形式)neednt have done 表示过去做了本没有必要做的事。should have done 表示过去该做但没有做(含有责备的意思)。shouldnt have done 表示过去不该做但做了(含有责备的意思)would have done 表示过去会做什么，而没有做。ought to have done 表示过去该做什么而没有做。(是职责和义务)might /may have done 表示过去或许、也许已经做了must do sth. / must be doing sth. 表示现在或将来一定在做什么。would like/love to have done sth. 表示过去愿意做某事，但未做成。would rather (not) have done 表示宁愿当时（没）做注意: could have done 表示（1）过去本来可以做实际未做（2）过去可能会will be 表示推测，主要用于第二、三人称，是对目前情况的推测(1)You could have done better, but you didnt try your best. (2)He cannot have been to that . (3)Can he have got the book? (4)He may not have finished the work.(5)If we had taken the other road, we might have arrived earlier.(6)You must have seen the film. You cannot have seen the film.(7)You neednt have watered the flowers,for it is going to rain.(8)You should have started earlier, but you didnt.(9)She shouldnt have taken away my measuring tape, for I wanted to use it.(10)I would like to have read the article，but I was very busy then.我本想读那本书，但我那时太忙了(11)I raised objections at the meeting, but now I would rather not have done it.注意: (1)should(ought to)+ have done 还可以表一种估计的情况，“按理会/估计会”He should have finished the work by now. 到现在他应该已经做完那项工作了。(2)didnt need to(have to)do :没有必要做而实际上也没有做I didnt need to clean the windows.My sister did it 2 hours ago.情 态 动 词 练 习编写人：何春霞一选择填空D1There was plenty of timeShe Amustnt have hurried Bcouldnt have hurried Cmust not hurry Dneednt have hurriedD2The plant is deadI it more water AWill give Bwould have given Cmust give Dshould have givenA3Tom ought not to me your secret，but he meant no harm Ahave told Btell Cbe telling Dhaving toldA4He you more help，even though he was very busy Amight have given Bmight give Cmay have given Dmay giveA5He at the meeting this morningHe was in hospital at the time Acouldnt have spoken Bmustnt have spoken Cshouldnt have spoken Dneednt have spokenC6He must be in the classroom， he? Amustnt Bcant Cisnt DcanB7You were driving at 100 km an hour，sir But officer，I My car cant go more than 80 Amay not have been Bcouldnt have been Cwouldnt have been Dneednt have beenA8Did you visit the famous museum? NoWe it，but we spent too much time shopping A.could have visited B.must have viste C.cant have visited D.shouldnt have visitedB9When can I come for the photos? I need them tomorrow afternoon They be ready by 12：00 Acan Bshould Cmight DneedD10You to the meeting this afternoon if you have something important to doAneednt to come Bdont need come Cdont need coming Dneednt comeD11There were already five people in the car but they managed to take me as well It a comfortable journey Acant be Bshouldnt be Cmustnt have been Dcouldnt have beenA12I think all drivers seat belts Ashould wear Bhad better wear Ccan wear Dhave to wearC13I to1d Sally how to get here，but perhaps I it out for her Ahad to write Bmust have written Cshould have written Dought to writeB14Peter come with us tonight，but he isnt very sure yet. Amust Bmay Ccan DwillA15A computer think for itself；it must be told what to do Acant Bcouldnt Cneed DwouldB16Jenny have kept her wordI wonder why she changed her mind Amust Bshould Cneed DwouldC17I heard they went skiing in the mountains last winter It true because there was 1ittle snow there Amay not be Bwont be Ccouldnt be Dmustnt beB18. I was really anxious about you. You_home without a word.A.mustnt have B.shouldnt have left C.couldnt have left D.neednt haveD19.Are you coming to Jeffs party? Im not sure. I_ go to the concert instead.A.must B.would C.should D.mightB20. Will you stay for lunch? Sorry, _. My brother is coming to see me.A.I mustnt B.I cant C.I neednt D.I wont二完成句子：1. “You must not smoke in the forest, or it will start a forest fire,” Rose said to the visitors. (smoke)“禁止在森林里吸烟，否则会引起森林火灾。”Rose对参观者说。2. The car must break down just when we were about to start off. (break) 我们正准备出发，车偏偏坏了。3. Bad luck! But for my illness, I must be seeing you off at the airport now. (see)运气真是太差了！要不是我生病，我现在一定在机场为你送行。4. Harry is feeling uncomfortable. He must have drunk too much at the party last night. (drink)Harry感觉不舒服。他肯定是在昨天晚上的宴会上喝多了。5. It cant/couldnt be the postman at the door. Its only six oclock.(be) 门外不可能是邮递员，现在才六点。6. We couldnt ask for a better babysitter. All our kids love her so much.(ask)我们找不到一个更好的保姆了，我们的孩子都那么的喜欢她。7. What a pity! We could have done better but there was a sudden power failure. (do)真遗憾！我们本来可以做到更好的，可是却突然停电了。8. The king of Prussia can/could never/not have imagined that his greatest gift to the Russian people would have such an amazing history.(imagine)普鲁士的国王决不可能想到他送给俄罗斯人民的这件伟大礼物会经历这么一段令人惊奇的历史。9. Mary cant/couldnt have referred to the dictionary, because she didnt give me an accurate explanation of the word. (refer) Mary一定没查过词典，因为她没给我这个词的准确解释。10. I cant thank you too much for all your help to my son while we were away from home (thank)对我们不在家时你对我儿子的帮助，我们对你怎么感谢都不为过。11. I neednt use a clock to wake me up because at six oclock each morning the train comes by my house. (use)我不必用闹钟来叫醒自己，因为每天早上六点钟火车都要从我的住所旁经过。12. As it turned out to be a small house party, we neednt have dressed up / neednt have been dressed so formally. (dress) 其结果不过是一个小型的家庭聚会，我们本不必要穿得如此正式的。13. In reality, you neednt have attached importance to that abstract theory. (attach)事实上，你本没必要看重那个抽象的理论。14. You dont have to buy a gift, but you can if you want to.(buy)你不必买礼物了，但你愿意的话也可以。15. One of our rules is that every student shall wear school uniform while at school.(wear)我们其中一项规则就是学生在校期间穿校服。16. Will you read me a story, Mummy? 妈妈，给我讲个故事好吗？OK. You shall have one if you go to bed as soon as possible. (have)好，如果你尽快上床睡觉，我就给你讲一个。17. I left my handbag on the train, but luckily someone gave it to the railway officials. How unbelievable to get it back! I mean, someone may/might have stolen it. (steal)我把手提包落在火车上了。不过，幸运的是，有人把它交过了乘警。把包拿回来是多么不可思议啊！我的意思是，有人本可能把你的包偷去的。18. Peter, if you dont like to swim, you might/ may as well stay (at) home watching TV. (well)Peter,如果你不想游泳的话，你不妨呆在家中看电视。19.Tom decided that anyone who stole his phone wouldnt/couldnt be so foolish as to use it right in front of him. (foolish)Tom觉得不管是谁偷了他的手机都不会愚蠢到在他的面前使用它。20. He didnt dare/dared not/darent/doesnt dare(to) ask for any more money.(dare) 他不敢再要钱了。虚 拟 语 气 练 习编写人：何春霞完成句子：1.If we had booked/Had we booked a table earlier, we couldnt be standing here in a queue. (book)如果我们当初早一些订餐桌，我们现在就不可能在这排队了。2.This printer is of good quality. If it should/were to break down/broke down within the first year, we would repair it at our expense.(break) 这台打印机质量很好。如果第一年出现质量问题，我们免费为您维修。3.If he had spent more time practising speaking English before, he would be able to speak it much better now. (able) 如果他以前花更多的时间练习说英语，他现在就会说得好多了。4.To tell you the truth, but for the fact that they were hard to team up with, I would have invited them to join us. (invite) 说实话，要不是他们不容易合作，我早就邀请他们加入我们了。5.We could have faced the difficulty together, but why didnt you tell me ? (face)我们本可以一起面对困难的，但是为什么你不告诉我呢？6.They set off for the destination too late; otherwise they wouldnt have been stuck in the storm. (stick)他们出发去那个目的地太晚了，不然的话，就不会困在暴风雨中了。7.Jack is a great talker. Its high time that he did something / he should do something instead of just talking. (do) Jack是一个大空谈家，到他该做事情而不是空谈的时候了。8.I couldnt have gone through that bitter period without your generous help. (go)没有你慷慨的帮助，我不可能熬过那段痛苦的日子。9.Luckily, we brought a road map with us without which we would have got lost. (get)幸运的是，我们随时携带了路线图，没有它的话，我们就迷路了。10.How I wish my house had not been sold . Its more valuable now. (sell)我是多么希望我没有卖掉我的房子。现在更值钱了。11.I failed my driving test. If only I had seized (on) the chance. (seize)我考驾照失败了。要是我