情態(tài)動(dòng)詞講義及練習(xí)

1、、“可以”、“需要”、“必須”情態(tài)動(dòng)詞 情態(tài)動(dòng)詞表示說(shuō)話人對(duì)某一動(dòng)作或狀態(tài)的態(tài)度，可以表示“可能” 或“應(yīng)當(dāng)”等之意。情態(tài)動(dòng)詞沒(méi)有人稱和數(shù)的變化。但不能單獨(dú)作謂語(yǔ)動(dòng)詞用，必須和不帶to 的不定式連用構(gòu)成謂語(yǔ)動(dòng)詞。只有情態(tài)動(dòng)詞 ought 要和帶 to 的動(dòng)詞不定式連用，在句中作謂語(yǔ)用。not 既構(gòu)成其否定式?，F(xiàn)將各將情態(tài)動(dòng)詞置于主語(yǔ)之前即構(gòu)成其疑問(wèn)式，在情態(tài)動(dòng)詞之后加情態(tài)動(dòng)詞的基本用法分述如下：1、can和could (could為can的過(guò)去式)的基本用法(1) 表示能力，女0: He can speak English better than you.(2) 在疑問(wèn)句和否定句中表示“懷疑”

2、、“猜測(cè)”或“可能性” ，表驚異、懷疑、不相信等態(tài)度 。主要用于否定句、疑問(wèn)句或感嘆句中。0: Can this green bike be Liu Dong's?Where can (could) they have gone to? 他們會(huì)去哪兒了呢？He can f (couldn t) be over sixty.他不可能超過(guò)六十歲。How can you be so careless? 你怎么這么粗心？(3) 表示“許可”時(shí) can 可以和 may 換用，0: You can (may) go home now.(4)表示請(qǐng)求對(duì)方的許可 ,0 : Can I go now?如

3、果要表示語(yǔ)氣婉轉(zhuǎn)，可用could代替can,這時(shí)could不再是can的過(guò)去式，0: Could you come again tomorrow?(6)can 和 be able to 都可表示能力, 兩者在意思上沒(méi)有什么區(qū)別。 但是 can 只能有現(xiàn)在式和 過(guò)去式，而be able to則有更多的形式， be able to指“經(jīng)過(guò)努力才能夠”。如: He will be able to do the work better.(7)can, could 后接完成式的用法：懷疑” 或“不肯定” 的態(tài)度， Could在否定句或疑問(wèn)句中表示對(duì)過(guò)去發(fā)生過(guò)的事情的he have said so?在肯定

4、句中，可以表示過(guò)去可能做到而實(shí)際并沒(méi)做到的事情，有“勸告”或“責(zé)備” 的語(yǔ)氣。如： When did you answer her letter? Only yesterday. It's too late. You could have answered it earlier, I am sure.(8) 用于肯定句中，表示理論上，習(xí)慣上，經(jīng)驗(yàn)上的, 理論上或是邏輯判斷上可能性 , 不是實(shí)際上的可能性 .Accident can happen at any time .It could be very interesting to do out for a drive .The te

5、mperature can fall to -60C , that is 60 °C below freezing.氣溫可降至 一60C,也就是零下 60CoHe can f (could n t) have eno ugh money for a new car.他不可能有足夠的錢(qián)買新車。You mustn t' smoke while you re Walking around in the wood. You could start a fire. 在林子里走時(shí)勿吸煙，那樣可能會(huì)引起火災(zāi)。(9) 用在過(guò)去時(shí)中，could經(jīng)常表示能夠做某事， 事實(shí)上不一定去做，而was

6、/ weaeble to則表示 過(guò) 去做成了某事 ”。在否定句中兩者可通用。He could swim across the English Channel. But he didn t fee' llike it that day. 他能游過(guò)英吉利海峽，但那天他不想游。Yesterday I was able to get home before the heavy rain. 昨天我在下大雨前趕到了家里。(10) can't 表示不可能； may not 表示可能不2、may和might (might為may的過(guò)去式)的基本用法(1) 表示允許 (第二人稱 )或征詢(第一人

7、稱 )對(duì)方許可，有“可以”之意，may 或 may not ，以避如： You may use my dictionary. 在回答對(duì)方說(shuō)“可以做某事”或“不可以做某事”時(shí)，一般多不用 免語(yǔ)氣生硬或不容氣。而用比較婉轉(zhuǎn)的說(shuō)法進(jìn)行回答。如： May I use this dictionary? Yes, please. 或 Certainly. 在請(qǐng)求對(duì)方許可時(shí)，如果Might I?就比用May I?語(yǔ)氣更婉轉(zhuǎn)些，阻止”或“禁止”對(duì)方做某事時(shí)，如： May I have a look at your new computer? 但是表示要用 must not 代替 may not，t. It &

8、#39; s too dangerous.、“可能”之意，如果用 might 表示如： May we swim in this lake? No, you mustn '(2)may 或 might 都可以表示推測(cè)，可能性，表示“或許” 可能性，則語(yǔ)氣更加不肯定，與can(表示理論上，經(jīng)驗(yàn)上，邏輯關(guān)系上)相比，may , might用于事實(shí)上的可能性 。如： They may (might) be in the library now . 一般情況下不用于疑問(wèn)句中 , 但 可以用于否定句中。 May not 表示“可能不” 之意， can not 表示“不可能” 之意。 The sto

9、ry may not be true.(3) 用于祈使句中表示祝愿，如：May you succeed.May God bless you(4) maymight as well do sth ,做也無(wú)妨，只好做某事，倒不如做某事,如： There is nothing to do ， I may as well go to bed.(5) may well 可能，很可能Liza _ well not want to go on the trip 一 she hates traveling.A. will B. can C. must D. may(6)may, might 后接完成式的用法m

10、ight ，語(yǔ) 表示對(duì)過(guò)去某事的推測(cè)，認(rèn)為某一件事情在過(guò)去可能發(fā)生了。如果使用 氣就比較婉轉(zhuǎn)或更加不肯定，如: Mary might have learned some Chinese before. 可以表示過(guò)去本來(lái)可以做到，而實(shí)際沒(méi)有做到的事情，有“勸告”或“責(zé)備”的語(yǔ) 氣，如: You didn't do the work well that day. You might have done it better.3、must的基本用法(1) must表示“必須”、“應(yīng)該”之意，其否定式must not,縮寫(xiě)形式為 must n't，表示“不應(yīng)該”，“不準(zhǔn)”、“不許可”或“

11、禁止”之意，如: We must study hard and make progress every day. You mustn't touch the fire.(2) 對(duì)以must提出的疑問(wèn)句，如作否定回答時(shí)，要用need n't或用don't (does n't) have to (不 必) 來(lái)回答，而不用 must n't，因?yàn)閙ust n't表示的是“禁止”或“不許可”之意，如: Must we finish the work tomorrow? No, you needn't (don't have to), bu

12、t you must finish it in three days.(3) 在肯定句中 must 可以表示推測(cè)，表示“一定”或“必定”之意， 如： Whose new bike can it be?了， It must be Liu Dong's. I know his father has just bought him a new one.(4) must 后接完成式的用法：表示對(duì)過(guò)去某事的推測(cè)，認(rèn)為某事在過(guò)去一定做到女0: Liu Dong isn ' t in the classroom. He must have gone to the library.(5) 在反

13、意疑問(wèn)句中，其后面的反問(wèn)部分取決于must 后面的動(dòng)詞形式：You must be a new comer ,aren'tyou?(6) if you must (dosth) 表示雖不贊同但可允許。 “0果你一定要那么做， 類似的句式有: whymust you? 為什么非要那樣做 Must you ? 非要那樣做嗎？， 表示說(shuō)話者對(duì)對(duì)方的堅(jiān)持生氣或不滿。If you must leave , do it quietly .Can I smoke ?If you must .偏偏”、“偏要 ”。(7)用于發(fā)生了某種于說(shuō)話人的愿望相反、不受歡迎的事時(shí)，意思是 Why must he d

14、o it that way?Why must it rain on Sunday?4、have to 的基本用法:(1) have to 和 must 的意義相近，只是 must 側(cè)重表示說(shuō)話人的主觀看法，而 have to 則表示 客觀需要，如: I must study hard .I had to give it up because of illness.(2) 在口語(yǔ)中，用 have got to 來(lái)代替 have to(3)have to 可以與其它的情態(tài)動(dòng)詞使用，但 must 不行5、ought to的基本用法should 強(qiáng)，比 must 弱，(1) 表示根據(jù)某種義務(wù)或必要或暗

15、理推斷“應(yīng)當(dāng)”做某事，語(yǔ)氣比 Should 側(cè)重從說(shuō)話人個(gè)人看法這一角度來(lái)講，傾向表示忠告。 例如： Everyone ought to obey the traffic reguIations.(2) 表示推測(cè)，注意與 must 表示推測(cè)時(shí)的區(qū)別：He must be home by now .( 斷定他已到家 )， He ought to be home by now .( 不十分肯定 )，This is where the oil must be.(比較直率)，This is where the oil ought to be.(比較含蓄);(3) “ought + have+ 過(guò)去分詞

16、”表示過(guò)去應(yīng)做某事而實(shí)際未做，有責(zé)備的含義。例如： Youought to have helped him. (but you didn 這時(shí)， ou'ght)t 與 should 可以互相換用。注意，在美國(guó)英語(yǔ)中 ought to用于否定和疑問(wèn)句時(shí) to可以省略。 例如： Ought you smoke so much?You oughtn 'stmoke so much.7、 dare 的基本用法(l)dare (dared 為其過(guò)去式 ) 作情態(tài)動(dòng)詞用時(shí)，主要用于否定句，疑問(wèn)句和條件從句中，如： Dared he bread the traffic regulations

17、 again?(2) 在現(xiàn)代英語(yǔ)中dare常用作行為動(dòng)詞，其變化與一般行為動(dòng)詞相同， 如： She dares to stay at home alone at night.We should dare to give our own opinion. 我們要敢于提出自己的觀點(diǎn)。He did not dare (to) look up. 他不敢抬頭看。I dare say he II come again.我想他會(huì)再來(lái)的。(I dare say為固定習(xí)語(yǔ))8、need的基本用法一， need 作情態(tài)動(dòng)詞用時(shí)，主要用于否定句和疑問(wèn)句中，特別是表示“必須，有必要”只 能用在疑問(wèn)句子中如： He n

18、eedn't worry about us now.二，need也可作為行為動(dòng)詞用，可用于肯定句，否定句和疑問(wèn)句中，其后可接名詞、代詞、 動(dòng)名詞或帶 to 的動(dòng)詞不定式為其賓語(yǔ)。如： You need to practise reading aloud every day.You don't n eed to do it yourself.你不必親自做這件事。We need to tell them the news. 我們需要把這消息告訴他們。Thetable needs painting (to be painted.). 桌子需要油漆一下。n eed n't后接完

19、成式可以表示過(guò)去做了一件本來(lái)不必要做的事情，如： Did you answer the letter yesterday? Yes, I did. But you needn 't have answered it.9、shall的基本用法一， shall 用作情態(tài)動(dòng)詞時(shí)， 用于第二、 三人稱， 表示說(shuō)活人的意愿， 可表示 （1） “命令” （2）（3）“警告” （4） 根據(jù)條例、規(guī)章、約定、合同應(yīng)盡的責(zé)任或義務(wù)， “強(qiáng)制”、“威脅” （5）鄭重的 “許諾”，“允諾”等意，如： He shall go first, whether he wants to or not.You shal

20、l do as I say. 按我說(shuō)的做。 （命令）You shall have my answer tomorrow. 你明天可以得到我的答復(fù)。 （允諾）He shall be sorry for it one day, I tell you. 有一天他會(huì)后悔的，我告訴你。 （警告） Nothing shall stop us from carrying out the plan. 什么也不能阻止我們執(zhí)行這項(xiàng)計(jì)劃。 （決心） 二，在疑問(wèn)句中， shall 用于第一、三人稱，表示說(shuō)話人的征詢對(duì)方意見(jiàn)或請(qǐng)求指示，如： Shall I open the door?10、should的基本用法一，

21、should 作為情態(tài)動(dòng)詞可以表示 “建議” 或“勸告”，有“應(yīng)該” 之意， 如： You should learn from each other.二， should 后接完成式表示過(guò)去沒(méi)有做到本來(lái)應(yīng)該做的事情，或是做了本來(lái)不應(yīng)該做的事 情。如： You should have give him more help.三，表示驚訝 ,吃驚 . 譯成 “竟然 ”To my surprise , my deskmate should have failed the exam. 四，用于 if 條件裝語(yǔ)從句中引導(dǎo)的與將來(lái)事實(shí)相反的虛擬語(yǔ)氣的句子中句子中fired, your health care

22、and other benefits will not be immediately cut off.A. Would you be B. Should you be C. Could you be D. Might you be11、 will 的基本用法(1) 用于各人稱，可以表示“意志”或“決心” ， 如： I have told him again and again to stop smoking, but he will not listen.(2) 在疑問(wèn)句中用于第二人稱，表示說(shuō)話人向?qū)Ψ教岢稣?qǐng)求或詢問(wèn)對(duì)方的意愿， 如： Will you please tell me how t

23、o get to the Capital Gymnasium?(3) will 可以表示目前，現(xiàn)在一種習(xí)慣性的動(dòng)作，有“總是”或“會(huì)要”之意，或不耐煩之 意。如： The boy will sit there hour after hour looking at the traffic go by.Every morning he will have a walk along this river.Fish will die out of water. 魚(yú)離開(kāi)水就不能活。 那男孩常常坐在那里好幾個(gè)鐘點(diǎn)，看著車輛行人通過(guò)。The door won t Open.這門(mén)總是打不開(kāi)。（生氣，不滿意）T

24、he ink won 'tcome out. （ 不耐煩 ）。12、would的基本用法“咅士”，如： He(1)would 作為 will 的過(guò)去式，可用于各人稱，表示過(guò)去時(shí)間的“意志”或“決心” promised he would never smoke again.(2)在疑問(wèn)句中，用于第二人稱，表示說(shuō)話人向?qū)Ψ教岢稣?qǐng)求或許問(wèn)對(duì)方的意愿時(shí)，比用 will 的氣更加婉轉(zhuǎn)，如： Would you like some more coffee?在日常生活中，學(xué)用“ I would like to”表示“我想要”或“我愿意”之意，以使語(yǔ)氣 婉轉(zhuǎn)，如： I would like to do

25、 Ex.2 first.(4)would 可以表示過(guò)去的習(xí)慣動(dòng)作，比 used to 正式，并沒(méi)有“現(xiàn)已無(wú)此習(xí)慣”的含義。 如： Last year our English teacher would sometimes tell us stories in English after class.During the vacation he would visit me every week. (5)表料想或猜想，如： It would be about ten when he left home.What would she be doing there?/ I thought he wo

26、uld have told you about it.(6) would 和 used towould 只表過(guò)去的情況。1) used to 表示過(guò)去與現(xiàn)在或過(guò)去某時(shí)與后來(lái)的情況有不同，而People used to think that the earth was flat.過(guò)去人們認(rèn)為地球是平的。 (現(xiàn)在人們不這么認(rèn)為。 )She would go out for a walk in the morning when she was in the country. 在鄉(xiāng)下時(shí)，她總是在早晨去散會(huì)兒步。 (可能現(xiàn)在仍有散步的習(xí)慣。 ) 2)used to可表示過(guò)去的習(xí)慣動(dòng)作和經(jīng)常的情況，而wo

27、uld只表示過(guò)去的習(xí)慣動(dòng)作。He used to / wouldmoke while writ in g.過(guò)去他寫(xiě)東西時(shí)常抽煙。She used to be fat. 她過(guò)去很胖13、used to, had better, would rathe的用法(1)used to 表示過(guò)去的習(xí)慣動(dòng)作或狀態(tài)，現(xiàn)在已不存在，在間接引語(yǔ)中，其形式可不變，例如： He told us he used to play foot ball when he was young .在疑問(wèn)句、 否定句、否定疑問(wèn)句或強(qiáng)調(diào)句中， 可有兩種形式。 疑問(wèn)句： Did you use to/ Used youto go to

28、the same school as your brother? 否定句：I usedn ' t to / didn' t use to go there.也可寫(xiě)n作 usen'；t) 否定疑問(wèn)句： Usen' tyou to/ Didn' tyou use to be interested in the theatre? 強(qiáng)調(diào)句： I certainly used to/ did use to smoke, but it was a long time ago. ；其反意疑問(wèn)句或簡(jiǎn)略回答中， 也有兩 種形式： She used to be very f

29、at. didn ' t she?/ use(d)n ' t she? Did you use to pYleasy, cIhdeids.s/?Used you to get up early in the morning? Yes, I did./ used to.(2)had better 意為“最好” ，后接不帶 to 的不定式， 例如： We had better go now . Yes, we had (we'd better/ we had better)./Hadn' t we better stop now? (Had we better no

30、t stop now?) I think I ' d better be go(用于進(jìn)行時(shí)態(tài)，表“最好立即” )You had better have done that (用于完成時(shí)態(tài)，表未完成動(dòng)作 ) 注： had better 用于同輩或小輩，對(duì)長(zhǎng)輩不可用。(3)would rather 意為“寧愿” ，表選擇，后接不帶 to 的不定式， 如： I ' d rather not say anything./Would you rather work on a farm?/ Wouldn ' t you rathertasy here? No, I would no

31、t . I ' d rather go there. 由于 would rather 表選擇，因 而后可接 than， 例如： I would rather work on a farm than in a factory.I would rather watch TV than go to see the film/I would rather lose a dozen cherry trees than that you should tell me one lie./I ' d rather you didn' t talk about this to（句n中O的

32、e. 'd rather 不是情態(tài)動(dòng)詞，would 在此是表愿望的實(shí)義動(dòng)詞 ），其后面必須用虛擬語(yǔ)氣，即過(guò)去時(shí)。專項(xiàng)練習(xí)（一）1. Iyou, because I thought I must be wrong.A. dare not ask B. dare not to ask C. dare not asking D. dare to not ask2. There some flowers in the garden.A. were used to be B. used to be C. uses to be D. used to be having3. “ take it ou

33、t? ” “ | smrry, you. ”A. Could couldn t B. Might might not C. Could -canD. Maycan t4. You were stupid to climb the tree. You hurt yourself.A. mayB. might C. will D. might have5. You those letters. Why didn t you ?A. should post B. should have posted C. must have posted D. ought to post.D. would get

34、not make it drink.C. maydaresD. dare can6. All the lights are on, the Smiths up.A. must get B. is getting C. must be getting7. He lead a horse to the water but heA. will can B. mayc anC. you mustD. you can8. “ Needwe do this job now?”“ Yes_, A. you need B. you should9. to have lunch with us today?A.

35、 Do you likesB. Would you likeC. Will you likedD. Have you liked10. He said that you watch TV all the evening if you wished.A. may B. must C. can D. mightnot. He likes driving his car.11. -s Joh n coming by train? -He should, but heA. must B. can C. need D. may12. Peter come with us tonight, but he

36、isn t very sure yet. A. must B. can C. may D. will13. Michaelbe a policeman, for he s much too short.A. need nt B. cant C. should nt D. wont'14. I thought yoube hun gry, so I have brought you some cakes.A. may B. might C. can D. couldthat to the teacher.15. I won der how heA. dare to sayB. dare

37、say ingC. not dare say D. dared say16. Come on! Wehurry because there isn t much time left.A. mayB. mustC. canD. n eed17. Amy did best in the En glish test. Shehard last week.A. must have work ing B. should have workedC. should workD. must work18. The fire sp read through the hotel very quickly but

38、every oneget out.with Barbara.A. had toB. wouldC. couldD. was able to19. I stayed at a hotel while in New York. -Oh, did you? YouA. could have stayed B. could stay C. would stay D. must have stayed20. It s nearly seve n o clock' .Jackbe here at any mome nt.A. mustB. n eedC. shouldD. can答案：1.A2.B

39、3.D4.D5.B6.C7.B8.C9.B10.D11.D12.C13.B14.B15.D16.B17.A18.D19.A20.專項(xiàng)練習(xí)（二）1.Jeanhave kept his pro mise. I won der why he cha nged his idea.A. must B. should C. n eedD. would2. Janenot find the exact time.解析：選B. “should have過(guò)去分詞”表示"過(guò)去本來(lái)應(yīng)該（但沒(méi)能）做某事” ；keep one ' s promis意 為“信守諾言”。have come to the

40、p arty, but sheA. could; couldB. might; couldC. should; couldD. should; would解析：選A. “ could have+過(guò)去分詞表示過(guò)去本來(lái)應(yīng)該（但沒(méi)能）做某事”。3. So many mistakes in your homework! You more careful.A. may beB. had to C. would beD. should have bee n解析：選 D. “You should have been more careful意為:你本來(lái)應(yīng)該更細(xì)心的。4. Her brother be at

41、home now, because he was seen playing basketball in the stadium justnow.A. must n tB. n eed n tC. can t D. should n't解析：選C. can t be at hom意為：不可能在家。5. -1 can t understand why our boss is lateHe the early bus.注意：canA. could miss B. may have missed C. can have missed D. might miss 解析：選B. “ may hav

42、e+過(guò)去分詞”表示對(duì)過(guò)去動(dòng)作的判斷，意為：可能做了某事。 表示可能時(shí)，只能用于疑問(wèn)句和反問(wèn)句。6. She did n't an swer the phone, sheaslee p.D. must have bee nA. may beB. must beC. should have bee n解析：選D.表示：對(duì)過(guò)去發(fā)生的事情的肯定推測(cè)。7. The little girl s eyes were red. She.A. may cryB. must cryC. must be cried D. must have been crying解析： 選 D. 意為：她剛才肯定一直在哭。

43、對(duì)過(guò)去某事正發(fā)生的推測(cè)。8 He his supper now, for the dining hall is still closed.A. can 't be havingB. needn 't be havingC. mustn 't be havingD. shouldn't be having 解析： 選 A. 對(duì)現(xiàn)在正在發(fā)生的事情的否定推測(cè)。9 I parked my bike behind the building, but now it is gone. It .A. may be stolen B. must be stolen C. must

44、 have been stolen D. must have stolen 解析： 選 C. 對(duì)過(guò)去發(fā)生的事情 的肯定推測(cè)的被動(dòng)式。10. Mr. Blackgo to work by ferry before the bridge was built?A. Did; used toB. Use; toC. Did; use to D. Does; use to解析：選C. used to do的疑問(wèn)式，可以是 Used+主語(yǔ)+to do ?或Did +主語(yǔ)+use to do?11. The hotel is only a stone's throw away, you take a

45、 bus.D. need notA. need not toB. not need toC. don't need解析： 選 D. 說(shuō)話人認(rèn)為不必要乘車 , need 為情態(tài)動(dòng)詞。12. I am busy now, my brother do it for you ?A. WillB.ShallC.MustD.May解析： 選 B. 在疑問(wèn)句中 shall 用于第三人稱，也表示征求意見(jiàn)。13. -You needn 't do it right now, need yo-u-?Yes I am afraid I _A. needB.needn 't C. mustD.

46、mustn't解析：選C. Yes的意思是：不。意為：恐怕我必須現(xiàn)在就做。14. My English-Chinese dictionary has disappeared . Who have taken it? （2003 年上海春季高考 ）A. should B. mustC. couldD. would解析： 選 C. could/can have done 用于否定推測(cè)和疑問(wèn)推測(cè)。（2003 年北京春季高考 ）15. -The room is so dirty.we clean it? Of course.A WillB. ShallC. Would D. Do解析： 選 B

47、. shall 用在疑問(wèn)句中，常用于第一，三人稱， 表示征求意見(jiàn)或請(qǐng)求指示。16. If you have something important to do, you waste any time.A. needn 't B. mustn 't C. may notD. won 't解析： 選 B. 根據(jù)句意用 mustn'there.17. If you want to borrow a football after school, your student card A. has to leave B. must leave C. has to be le

48、ftD. must be left解析： 選 C. have to 表示客觀需要， must 表示主觀需要。學(xué)生證必須放在此是客觀需要。18. “ Did you scold him for his carelessness?“Yes, but” it ”?A. I 'd rather not doB. I 'd rather not have done C . I shouldn 't do D. I 'd better not do 解析： 選 B. would rather 加完成時(shí)表示對(duì)完成了的或過(guò)去了的事情的態(tài)度。 意為： 當(dāng)時(shí)是不情愿 做的。19.

49、“ Don 't get near to it . It is too dangerous!A. Yes, I won 't B. No, I don ' tC. No, I can'tD. No, I won解析：選D. A為錯(cuò)誤的表達(dá)方式；B和C沒(méi)有直接回答對(duì)方的問(wèn)候。20. He must be in the classroom, he?A. mustn 'tB. can 't C. isn 't D.can解析：選 C. 對(duì)表否定的 must 進(jìn)行反意疑問(wèn)時(shí)，要用句子的實(shí)義動(dòng)詞be in the garden. He must b

50、e in the room. A. can 't B. mustn 't 解析：選A.否定推測(cè)用can'不用21. HeC. will not mustn'tD. may not22.“Do you have to leave now?B. haveA. can 't 解析：選 D.23. “Let '“”Iam very sorry, but I reallyC. should D. must回答have to的疑問(wèn)句用must作肯定回答?！盻? ”s go to the library, shall we? B. Yes, I willA.

51、No, I can解析：選 D. A,B,C 都不能回答 shall we,”“ You _C. Yes , thank youD. No, we 'd better not此處 D 的語(yǔ)氣比較婉轉(zhuǎn)客氣。24. “Can I take it away? A. shouldB. could解析：選 D. had better 與不帶better not.C. would D. hadto 的不定式構(gòu)成謂語(yǔ)，可以變成疑問(wèn)句：Hadn't you bette-r-25. Youhave brought your camera. They all had theirs with the

52、m.D. mustn 'tA. couldn 'tB. needn 't解析：選 B. 本來(lái)不必要做某事 .C. wouldnit be May?A. MayB. Must C. Can解析：選 C. 表推測(cè)時(shí) A，B 都用作疑問(wèn)句。27. John be a basketball player. He is much too short.A. mayB. mustn 't C. can 't解析：選 C. 斷然的不定推測(cè)用 can't26. See who is there!D. WillD. shouldbe ill.D. need28. T

53、he Chinese teacher looks so pale. She _ A. mustB. mustn 't C. can解析：選 A. 表示有把握的肯定推測(cè)用 must29. Somethingto save our earth. Do you think so?D. must be doneA. can doB. must doC. has to do解析：選D. “something must be done意為：必須采取措施。30. Look at what you have done! You be more careful.A. ought B. canC. wou

54、ldD. should解析：選 D. ought 后應(yīng)用 to專項(xiàng)練習(xí)（三）1. Has Li Lin started? He said he would join in the party. He . He is a man of keeping his word.A. could have left B. must have left C. can 't come D. won 't be comngi2. May I park my car here? No, you . No car is allowed to park here.A. may not B. n eed

55、n 't C. mustn 'tD. daren 't3. Excuse me, could you tell me where the Yajia Supermarket is? It ' s two blocks straight ahead. You miss it.A. mustn 'tB. can 'tC. needn 'Dt. shouldn 't4. I saw Mr. Sun at Tongyu Station this morning. You . He ' s still on holiday in H

56、awaii.A. c ouldn 't haveB. mustn 't haveC. shouldn 'tD. needn 't5. How about paying a visit to Dr. Wang, our former Chinese teacher? Good idea. I will e-mail him today so that he know to expect us.A. shall; whyB. could; when C. would; whatD. will; how6. Everything has two sides. Beau

57、tiful songs, sometimes, be just noise to others.A. must B. may C. should D. could7. Someone my umbrella. I found it wet yesterday.A. must be using B. must have usedC. must use D. must have been using8. How dangerous it was! Yes, but for the passer-by ' s quick action, the girl .A. was drowned B.

58、 could have been drowned C. had drowned D. should be drowned9. Youhurt him.scold such a pupil who always keeps silent so seriously that youA. should; canB. may; will C. mustn ' t; may D. can ' t; must10. Why does Alice know so much about Angkor Wat? She have been there, or .A. must B. oughtn ' t tCo. m