情态动词canmaymustneed及练习

1、考点二： 情态动词 can 的用法，表示某人能做某事。肯定句：主语+ca n+动词原形+其他I can play the piano .否定句：主语 +can +not（can 't）+ 动词原形 +其他I can not （can 't） play the piano . 一般疑问句： Can + 主语+动词原形 +其他?Can you play the piano?特殊疑问句：特殊疑问词 + can + 主语+动词原形 +其他?What can you play ?can play the piano情态动词 must, can, could, may, might表推测的

2、用法：情态动词中的 must, can, could, may, might 都表推测。其中 must 的可能性最大， can / could 次之， may / might 最小。具体用法如下：1. must 的用法（1）表示推测“可能性”时，意思是“一定、准是”，语气较肯定，较有把握。He must be American. = It is certain that he is American. 他 准 是 个美国人。（2） must表推测只能用于肯定句。如果要表示"一定不、肯定不”的意思时，应用can't, 如询问某种可能时，应用 can。Hemust know my

3、 address.他肯定知道我的地址。（一定）Hecan'tknow my address.他肯定不知道我的地址。（一定不）Canheknow my address?他知道我的地址吗？（询问可能性）（3） must 表示推测时，可以推测现在 /正在发生的动作 / 过去发生的动作。He must have a car now. （现在）他一定有辆小汽车。Hemustbe doing hisexercisesin the classroom. （正在进行）他一定在教室里做练习。Hemusthave finishedthe work.（过去发生）他一定已完成了工作。注：must 表 示推测

4、时很少用 于将来 的 情况。 一般 不用 He must come tomorrow. 可 用 It's certain/ I'm sure that he will come tomorrow.（4）在反意疑问句中，当附属部分含有表示推测意义的must 时，疑问部分的助动词应与must后面的动词在非推测情况下的用法保持一致。Hemustbe aworker,isn'the?（现在）他准时个工人，是吗？Itmusthaverainedlast night,didn'tit? （过去）昨晚一定下雨了，是不是？YoumusthavelearnedEnglish fo

5、rmanyyears, haven'tyou? （完成时）你一定学了好多年英语，是吗？2. can / could 的用法（ 1） can 表示推测“可能性”时，往往用于否定句或疑问句。Can't "定不”，语气很肯定。can在疑问句中意思是"会、可能”。He can't be at home. = It is impossible that he is at home. 他一 定不在家。（2）can /can't 后可接进行时 / 完成时，表示对现在发生的动作或过去发生的动作进行推测。They can't be readingin

6、the library. 他们一定不在图书馆读书。He can't have gone to Shanghai forI saw him a minuteago.他不可能去了上海，我刚才还看见他。It's so late. Where can she have gone? 天晚了，她可能去哪儿了呢？（3） 在反意疑问句中，当陈述部分含有表示推测意义的can't 时，疑问部分的助动词应与 can't 后面的动词在非推测情况下的用法保持一致 .He can't be a teacher, is he? 他不是教师，是吗？She can't have

7、finished her homework, has she? 她一定没有完成家庭作 业，是不是？（4）could 可用于表示某事有可能发生或可能是事实。Don't eat it. It could be poisonous. 不要吃它，可能有毒。The plane could be delayed by fog. 飞机可能会因为雾晚点。（5）could 还可以用于表示客气、委婉、礼貌的请求语气。Excuse me, could you tell me the way to the bus station? Could y ou help me?（6）couldn't 表示否定

8、推测，表示某事不可能真实，或由于特定事实或环境某事肯定不会 发生。It couldn't possibly be poison. 这不可能是毒药。注：有时与形容词的比较级连用强调某人或某物不可能再更多地具有某种属性。You could n'tbe more wrong.你真是大错特错。Icould n'tbe happier.我简直是幸福极了。3. may和might的用法、“也许”，语气没有 must（ 1） may, might 表示推测“可能性”时，意思是“可能”He may / might be American. = It is possible that h

9、e is America n. 他可能是个美国人。注：might不表示过去时态，只是语气上比may更委婉，表示的可能性更小。（2）may, might 表推测时，可以用于否定句，意思是“可能不、也许不” ，但不用于疑问 句。He may / might not be at home. 他也许不在家。3）may, might 可以推测现在正在发生的动作或过去发生的动作。He may / mightbesleepingnow.现在）他可能正在睡觉。The boy may /mightnot bewatchingTV at home.（现在）这个男孩可能没在家看电视These studentsmay

10、/ mighthaveseenthe filmbefore. （过去）这些学生以前可能看过这部电影。4）may, might 还可以推测将来的情况。thinkwe shouldtake raincoatwith us, it may rain. 我想我们应该带上雨衣，可能要下雨了。She mightnot comethisafternoon.她今天下午可能不来了。Exercises:Completethesentences“t ?using “ must”or、丄 ”can't ”1. I havetried tocallhim atthe office,butthere is no

11、reply.She be very clever.2.Theyhave boughta new car.They have alotof money3.Sheis carryinga Japanesenewspaper. ShebeChinese.4.Hegoes abroada lot,Hehave an importantjob.He be athome.5. She isa professorat the university.6. She is acting in a Shakespeare play tomorrow. She be an actress.随堂练习】选择填空1. I

12、thought youlikesomething to read.So Ihave brought yoA.oughtB.mightC.couldD.must2.-Thatmanmust beSarah'shusband.-No,he_be herhusband.She isstillsingle.A.can'tB.mustn'tC.may notD.ought to3.Peter_come with ustonight,buthe isn'tvery sureA.mustB.may C.canD. will4.What_itbe?u some book.Itb

13、e a car.A.can;can't;mustB.can; can; mustC.can;mustn't;mustD.must; mustn't;5.Look,someone iscoming. Guess .-Jack.He'salways on time.A.whocanit beB.who he mayC.whohecan beD.who it can be6.-IsawMary inthe libraryyesterday.-Youher. Sheis stillabroad.A.mustn'tseeB.can't have seenf

14、or-Itbe a mailitiscanC. must n'thave seenD. couldn'tsee7. David, youplay with the valuable bottle,youbreak it.A.won't;can'tB.mustn't; mayC. shouldn't; must D. can't; shouldn't8.Susanrefuses tomarryJacknow. She her mind.A. must change B. should have changedC. must have

15、 changedD.would have changed9. Sue come together with us tonight, but she isn't very sureyet.A. must B. may C. need D. will10. Aunt Margaret the rai n, otherwise she would have arrived here by now.A.must have missed B. shouldhave missedC. had missedD. mightmiss1. Who is the man over there? Is it

16、 Mr. Wu?Ithim, but I am not quite sure.A. may beB. maybe C. isD. must be2. Some people feel sickwhen they read a book in a car or on a boatA. mustB. shouldC. mayD. need3. -Must I go to medical school and be doctor like you, Dad?-No, you, son. You ' re free to make your own decision.A. can '

17、tB. mustn ' tC. shouldn ' tD. don ' t have to考点：考查情态动词辨析。4. You be hungry after the long walk. Help yourself to some cakes.A. should B. must C. n eed to D. ought to5. Could you pleasethe piano so loudly? Your brother is having a rest now.A. not to playB. not playC. don ' t playD.to n

18、ot play6. That pink T-shirt with Ping An ' s picture on itbelong to Miss Ma. Sheadmires him a lot.No, itbe hers. She hates pink colour.A. mu st, can ' t B. may, can ' tC. can, mustn ' t D. must, mustn 't7. -Must I answer it in English?-No, you. You can use Chin ese.A. shouldn 

19、9; tB. can ' tC. mustn ' tD. needn ' t8. -we go swimming in Xishuanghu Lake today? Oh, no .It' scold to swim on such days. I will catch a cold.A. Will; veryB. Will; tooC. Shall; very D. Shall; too9. People who drink wineto drive after May Day.A.don' t allowB.isn ' t allowed C

20、.mustn ' t allow D. mustn' t be allowed10. I was asked to attend the meeting before eight.Oh, you. I'm sorry for not tell ing you that we have cha nged the pla n.A. must B. can't C. may D. need n't11. You have worked for a long time. Yoube very tired.A. mustB. can' tC. couldD

21、.must n't12. -Can I ask you a question?-No, you. Youto ask me questi ons duri ng exams.A. can ' t, mustn ' tB. can' t, aren ' t supposedC. can, aren ' t supposed D.can, don' t have13. Whatyou do if youin Grade 7 now?A. could, areB. would, are C. could, was D. would, were【

22、答案】D14. This CDbelong to Bill. It has his name on it.A. mustn ' t B. might C. can' t D. must【答案】D15. You drive your car so fast. It' s dangerous.A. wouldn ' t B. shouldn ' t C. couldn ' t D. mightn't【答案】B16. Shall we meet at the station at 8 a.m?In fact we.The trainun til

23、 10a.m.A.mustn' t ;doesn ' t leave B.mustn' t ;leavesC.needn' t ;won ' t leave D.needn' t;will leave【答案】C17. -Mum,I watch TV?-No. Un less your homework.A. could; fini shesB. can; will finishD. can; will be fini shedC. may; is fini shed【答案】C18. - Look! A man is cutting a tree

24、on the moon.-Itbe true. The teacher said there is no air on the moon.t D. must nSorry, IA. can ' tB. may not C. shouldn【答案】A19. you please play tennis with me?A. Could; can 'tB. Could; couldn ' tC. Can; don 'tD.Can;couldn 't【答案】A20. -I broke the window.-Youplay football n ear the

25、 win dow.A.shouldB. shouldn ' tC. had better【答案】B21. you swim? Yes, but I ' m not a good swimmer.A. CanB. MayC. NeedD. Must【答案】A22. Is the woma n over there Miss White?Itbe her. She ' s gone to Hangzhou.A. mustB. can ' tC. needn ' t D. may【答案】B23. Can your friend sin g?-.A.Yes,I

26、can B.Yes, he can C.No,she can D.No,I can ' t【答案】B24. Where is KateA. May【答案】C【解析】25. Sheshe is clea ning the classroom.B. May beC. MaybeD. CanA. would【答案】 【26.- -I 'come to the party, but I am not quite sure.B. shouldC. mightD. mustAre you coming to Davy ' s party, Kate ?m not sure, Igo

27、 to the movies in stead.A. wouldB. should C. might【答案】C27. It's the library! So you_A. must n'tB. won't【答案】A【解析】28. Look at the sign! It says “No Smoking!” YouA. mustn 'tB. ought not toC. needn 't【答案】A29. -May I watch TV now. Mum?-No, you. Youdo your homework first.A. don't;

28、mustB. don't; can'tC: can't, must【答案】C30. There' s somebody at the door. Whoit be? Is it the postman ?No, itbe him. It ' s just seven o ' clock. It ' s too early.A. may, can 'tB. will, won 'tmay, mustn ' tD. must, may not【答案】Amake any no ise here.C. needD. mustD. maysmoke here.ItD. donD. can't;s dan gerous. t have tocanC.31. -you sing an English song?-Yes, I can.A. CanB. MayC. MustD. Need【答案】A32. Is Joh n co