初中英语语法专项习题11.情态动词

1、情态动词讲义 情态动词讲义 I. 情态动词的语法特征 情态动词本身虽有词义，但只表示说话人的看法，命令，准许等；不能单独作谓语，须与实义动词构成谓语 1） 情态动词 除ought to，have to， used to外，其它情态动词后面只能接不带to 的不定式。 2） 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。 3） 情态动词没有非谓语形式，即没有不定式to，分词-ing,-ed等形式。 4） 情态动词类别：can/cannot/can not/cant, may/may not, must/ mustnt, shall/shall not/ shant, should/

2、shouldnt, ought to/ oughtnt to, will/ wont , would/ wouldnt. need/ neednt, dare/darent, used to/ usednt to/ didnt use to, have to/ dont have to, had better/ had better not, would rather/ would rather not II. 一些容易混淆的用法 1. 比较can 和be able to 1）can/could 表示能力(born ability, learned ability), 只用于现在式和过去式(c

3、ould)。 be able to可以用于多种时态。 People can speak. He can speak English fluently. A computer cant think for itself. It must be told what to do. He said he could do the work by himself. cf: They will be able to tell you the news soon. 他很快就能告诉你消息了。 He said he would be able to get a passport soon. He had bee

4、n able to speak a little Chinese before he came to China. 2）只用be able to 表示经过努力或在一定条件下设法成功地做了某事时，而非能力，只能用was/were able to， 不能用could。-managed to do sth./ succeeded in doing sth. He was able to flee Europe before the war broke out. = He managed to flee Europe before the war broke out. After two years

5、of hard work, he was able to speak English. Although the driver was badly hurt, he was able to explain what had happened. With the help of the firemen, they were able to leave the burning house. 3) could不表示时态 (1) 提出委婉的请求，（注意在回答中不可用could）。 - Could I have the television on? - Yes, you can. / No, you c

6、ant. II. 比较have to和must 1)两词都是必须的意思，have to 表示客观的需要， must 表示说话人主观上的看法，既主观上的必要。 My brother was very ill, so I had to call the doctor in the middle of the night. 我弟弟病得很厉害，我只得半夜里把医生请来。(客观上需要做这件事) I want to take more exercise, so I must walk to school every day. 2） must 表示必须，必要，一种义务，责任，职责,命令等语气 e.g. We

7、must obey the school regulations. You must respect the old. You must come here early tomorrow. I am afraid I must be leaving. We must stay home, mustnt we? 3）表示必然，必定,不可避免的结果 Man must die. 表示固执，一定要，坚持要 e.g. Our three-year-old boy must do the opposite to what we ordered. Why must you interrupt me now

8、and then while I am speaking. Must you shout so loudly? 表示过去的不巧，偏偏 e.g. Just when I was busy, the neighbor must come and chat. As I was sitting down to dinner, the telephone must ring. 4）have to有人称、数、时态的变化，而must只有一种形式。 e.g. He had to look after his sister yesterday. You will have to go there alone.

9、5） must 问句的回答 e.g. Must I wait until they come? -Yes, you must.-No, you neednt./ dont have to/ dont need to Must we hand in our English exercise books today? -_. / _ 6） 在否定结构中： dont have to 表示不必 mustnt表示禁止， 不允许，带有很强的语气 e.g. You dont have to tell him about it. 你不一定要把此事告诉他。 You mustnt tell him about i

10、t.你一定不要把这件事 Cars mustnt be parked here. III. may 表示给予许可 1) You may sit here. May I borrow your books? Might I have your telephone number? 2) can/could 和 may/might . can和 may都可表示请求，或给与许可。Can 语气一般，could/may 比较礼貌，常用。对于can/could的回答,一般是can/cant,不可用could，而对may的回答，则是may/may not。 -Could I use your legtop? -

11、Yes, of course you can./ Sorry, I am afraid you cant . -May I leave the classroom? -Yes, you may. / No, you mustnt/you may not/ you dont have to. IV. 情态动词can, could, may, might, must表示推测的用法 1) can/ could (1). Can / could 用于疑问句表示猜测，可能,could 一般不表示时态，只表达委婉语气. Where is he now? Can he be reading in the l

12、ibrary? Where can they have gone? (2). Can 可表示理论上的可能性或偶尔的可能。 You can walk miles and miles through the forest without meeting anyone. He is very clever boy , but he can be dull sometimes. Even experienced teachers can make mistakes. (3) cant / couldnt 表示不可能; Couldnt 一般不表示时态，只表达委婉语气. 但在过去时态的宾语从句只能用cou

13、ldnt. I believe him. He cant e such an irresponsible man. She cant have gone to school. We have no school today. I thought you couldnt have met her yesterday. 2) may/might (1) may/might用于肯定句，表示没有把握的推测； might 表示推测时，不表示时态, 只是可能性比may 小, 但在过去时态的宾语从句只能用might. Peter may come with us tonight, but he isnt v

14、ery sure yet. He might be at home. It may have drizzled during the night. Philip may (might) have been hurt seriously in the car accident. (2)may not / mightnt 表示可能不，也许不。 He may not know the truth. 3） must must用在肯定句中表示较有把握的推测，意为一定。 You have worked hard all day. You must be tired. He must be working

15、in his office. 他一定在办公室工作呢。 I didnt hear the phone. I must have been asleep. 4) 这些表示推测的情态动词使用时的时态构成 （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. （2）情态动词+动词现在进行时。 表示对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。

16、（3）情态动词+动词完成时。 表示对过去情况的推测。 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时。 表示对过去正在发生事情或一个完成进行的动作的推测。 Your mother must have been looking for you. 你妈妈一定一直在找你。 5表示推测的情态动词语气的强弱 肯定语气-由强至弱 must may might 否定语气 -由强至弱 cant couldnt may not might not 疑问语气 can 6) could have

17、 done 有两种含义。 其一，表示本来有能力做但实际上没有； 其二，表示差点就，幸亏没， 带有幸而没发生的语气。 I could have walked to the station if I had known it was so near. You were stupid to throw the box out of the window. It could have hit someone. V. ought to , should 1) 也可表示较大的可能性，（推测） If he started at six, he ought to/ should be there now. I

18、t is nearly seven oclock now. Jack should be here at any moment.（应该，该） 2） 表示义务，责任, 都为应该的意思，可用于各种人称。表示要求，命令时，语气由 should（应该）、had better最好）、must（必须）渐强。 -Ought he to go? -Yes. I think he ought to. We ought to/ should listen carefully in class. You should be more careful in crossing the street. You ought

19、 to leave now if you dont want to miss the train. 3） should用于第一人称，表示说话人的谦逊，客气，委婉的语气 You are mistaken, I should say. 依我看，你是搞错了 I should advise you not to do that. 我倒是劝你别这样做。 4） should用于引导的条件从句中，表示一件事听起来可能性很小，相当于“万一” Ask her to ring me up if you should see her. If you should change your mind, please l

20、et us know. Take a thick coat in case it should get/ gets cold. 5) 用于动词ask, advise, command, demand, insist, intend, recommend, request, require, suggest, urge, order等之后的从句里，表示命令，忠告，要求，建议， (should)+ do / be done. The general ordered that his men (should) fire. The doctor urged that he( should) be op

21、erated on as soon as possible. He insisted that I should pay him the money. 7) 用于形容词之后的从句里， 这样的形容词有important, essential, necessary, natural，用 (should) + do/ be done It is essential that every child should have the same educational opportunity. 8) why/ how should.结构中，表示说话人对某事不理解，感到意外，惊异等意思，意为“竟会” Why

22、 should you be so late today? 你今天怎么来得这么晚？ -Where is Betty living? -How should I know? 我怎会知道 I dont know why you should think that I did it. 我真不知道你凭什么认为这是。 9） should / ought to have done 表示本应该做而事实上未做某事，否定句表示不该做某事而事实上做了。 You ought to (should) have been more careful in this experiment. He ought not to

23、have thrown the old clothes away.（事实上已扔了。） You shouldnt have cheated in the exam. ought to 在语气上比should 要强。 VI. need的用法 1） 肯定句中作实义动词 He needs to take a rest. He needs some time to think it over. The recorder needs repairing/ to be repaired 否定句中，作情态动词和实义动词 You neednt / dont need to do the exercise if

24、you find it too easy. -Need we stay behind after school? -Yes, you must. / No, you neednt -Do we need to stay behind after school? -Yes, we do/ No, we dont 2) neednt have done sth 本没必要做某事,但实际做了。 I dressed very warmly for the trip, but I neednt have done so. The weather was hot. There was plenty of t

25、ime. She neednt have hurried. You neednt have come to school. It is a holiday today. Cf: neednt have done / dont need to I didnt need to go to school that day as it was Sunday. We neednt have brought a camera with us. He has got one. He said that he would bring a camera with him, so I didnt need to

26、bring mine. VII. Dare 1) 情态动词: dare/ dared + do , 否定形式为dare not/ dared not, 用于疑问，否定，条件句中 How dare you lay your hand on me? Dared he leave without permission? I wonder how he dared say that to the teacher. He dare not walk alone at night. I dared not go any further. If you dare do such a thing, you w

27、ill get into trouble. 2) 实义动词：dare + to do,有时态，人称和数量的 变化；否定句，疑问句需用其他助动词的辅助, 否定句中to可省略。 He dares to do anything . / The little girl dares to speak before a large audience. I dare say he will fail. I wouldnt dare( to) interrupt him. He doesnt dare (to) walk alone at night. Does he dare to walk alone a

28、t night. He stood there, not daring to raise his head. VIII. shall, will 1) shall 用于疑问句，第一，三人称，表示愿意效劳以征求同意，或提出建议征询意见。 Shall I carry the luggage for you, Miss Li? Shall we have a meeting this afternoon? Someone is waiting for you ? Shall he come in? 2) 用于第二，三人称陈述句中，可表示说话人给对方的命令，承诺，警告或恐吓等。 Nothing sha

29、ll stop us from doing good. Everyone shall fight to death. You shall fail if you dont work harder. He shall have the book when I finish reading. 3) will (1) 表示主语的愿意, 决心, 承诺. If you will listen to me, I will help you. (2) 表示物体的属性,或人或动物的习性. The door wont open. Oil will float on water. Fish will die ou

30、t of water. The man will get angry over nothing. (3) 表示没有固定时间的习惯. I will sometimes sit up late for exams sake. IX. used to would 1)都可表示过去习惯，但used to强调过去经常或习惯于做某事，但现在已不做了，强调与现在的对比，而 would 单纯就表示过去的习惯行为 Illiteracy is still a problem, but it used to be worse. Sometimes she would bring me some small pres

31、ents when she was in a good mood. 2)used to 的否定形式是usednt to do / didnt use to do There used to be a tall tree here, usedn there/ didnt there? XI. had better表示最好 had better 相当于一个助动词，它只有一种形式，它后面要跟动词原形。 had better do sth / had better not do sth It is pretty cold. Youd better put on my coat. Shed better

32、 not play with the dog. had better have done sth表示与事实相反的结果，意为本来最好。 You had better have come earlier. would rather表示宁愿 would rather do / would rather not do would rather do than do 宁愿而不愿。 还有would sooner, had rather, had sooner都表示宁愿、宁可的意思。 If I have a choice, I had sooner not continue my studies at th

33、is school. I would rather stay here than go home. = I would stay here rather than go home. 典型例题 -Shall we go skating or stay at home? -Which _ do? A. do you ratherB. would you rather C. will you rather D. should you rather 答案B。本题考查情态动词rather的用法，would rather +do sth 意为宁愿，本题为疑问句，would 提前，所以选B。 XII. 一些

34、特殊含义和用法 1may 1) may 放在句首，表示祝愿。 May the world be full of love. May God bless you! 2) may 可用于让步状语从句中. Whatever faults he may have, selfishness is not one of them. However much he may admire her, he will never ask her to be his wife. 3) may/might as well，后面接不带to 的不定式，意为不妨。 If that is the case, we may a

35、s well try. (cf: might do well to do sth. , had better do) 2. can 的惯用语 1） can but do 只好 We can but do our best. 我们只好尽全力了 2） cannot( choose / help) but do 不得不 ( cant help doing) I cant help but admire your courage. I cant choose but realize that I am wrong. 3） cant help doing不禁 I cant help liking her

36、 though she can be annoying sometimes. 4） cant too 无论也不过分,越越好 We cant be too careful while driving. 5) as as can be 。 得不能再，极为 She is as happy as can be. 她再快乐不过了 6) asas one can -asas possible 典型例题 1）-Could I borrow your dictionary? -Yes, of course, you_. A. mightB. will C. can D. should 答案C.could表示委

37、婉的语气，并不为时态。答语中of course，表示肯定的语气，允许某人做某事时，用can和 may来表达，不能用could或might。 2）-Shall I tell John about it? -No, you _. Ive told him already. A. needntB. wouldntC. mustntD. shouldnt 答案A。neednt 不必，不用。 wouldnt 将不, 不会的。 mustnt 禁止、不能。 shouldnt不应该。本题为不需要，不必的意思，应用neednt。 3）-Dont forget to come to my birthday par

38、ty tomorrow. -_. A. I dont B.I wont C. I cantD. I havent 答案B.will既可当作情态动词，表请求、建议、也可作为实义动词表意愿、意志、决心，本题表示决心，选B。 Tom ought not to _ me your secret, but he meant no harm. A. have toldB. tellC. be tellingD. having told 答案A。由于后句为过去时，告诉秘密的动作又发生在其前因，此地应用过去完成时，但它在情态动词 ought to 后，所以用have。 请试做下面几题,呵呵.4) Be qui

39、ck! They _ for us at the school gate now. a. must have waited b. must wait c. must be waiting d. ought to have wait 5) Its getting dark, so we _. a. should stay outside b. had better not to leave c. might as well leave d. ought to be left 6) He _ the championship, but he got injured five minutes aft

40、er the game started. a. might win b. might have won c. can win d. can have won 7) We _ last night, but we went to the concert instead. a. must have studied b. might study c. should have studied d. would study 8) The fire spread quickly but everybody _ escape in time. a. was able to b. would c. could

41、 d. might 9) Did you criticize him for his mistakes? Yes, but _ it. a. Id not rather do b. Id rather not have done c. I ought not to do d. Id rather not do 10) Ive tried many times, but the car just _. a. wont start b. wouldnt start c. doesnt start d. didnt start 初中英语语法专项习题1 ( ) 1 John_ come to see

42、us tonight, but he isnt very sure yet.A. may B. canC. has to D. must( ) 2 They _ do well in the exam.A. can be able to B. be able toC. can able to D. are able to( ) 3 -May I take this book out?-No, you_.A. cant B. may not C. neednt D. arent( ) 4 You_ go and see a doctor at once because youre got a f

43、ever.A. can B. must C. dare D. would( ) 5 -Can you speak Japanese?-No, I_.A. mustnt B. cant C. neednt D. may not2 ( ) 1 -He_ be in the classroom, I think.-No, he _ be in the classroom. I saw him go home a minute ago. A. can; may not B. must; may notC. may; cant D. may; mustnt( ) 2 -Shall I get one m

44、ore cake for you, Dad?-Thanks, but you_, Ive had enough.A. may not B. must not C. cant D. neednt( ) 3 Even the top students in our class cant work out this problem, so it be very difficult.A. may B. must C. can D. need( ) 4 He isnt at school. I think he _ be ill. A. can B. shall C. must D. has to( )

45、 5 _ I take this one?A. May B. Will C. Are D. Do3 ( ) 1 The children_ play football on the road.A. cant B. can C. mustnt D. must( ) 2 You _ be late for school again next time.A. mustnt B. needntC. dont have to D. dont need to( ) 3 -Must I do my homework at once?-No, you_. A. neednt B. mustnt C. cant D. may not4 ( ) 1 His arm is all right. He_ go and see the doctor.A. has not to B. dont have toC. havent to