情態(tài)動(dòng)詞歸納及專項(xiàng)練習(xí)題

1、情態(tài)動(dòng)詞歸納及專項(xiàng)練習(xí)題一、單項(xiàng)選擇情態(tài)動(dòng)詞1. If we had paid enough attention to the issue of the heavily-overloaded vehicles, the tragedy of the collapse of an overpass in Wuxi avoided.A. shouldB. could beC. should have been D. could have been【答案】D【解析】【詳解】考查情態(tài)動(dòng)詞用法。句意：如果我們對(duì)超載車輛問題給予足夠的重視，就可以避免無錫立交橋垮塌的悲劇。本句為 情態(tài)動(dòng)詞+have don

2、e”結(jié)構(gòu)，結(jié)合句意表示 本來可以；本來能夠 應(yīng)用could have done結(jié)構(gòu)，且主語與謂語動(dòng)詞 avoid構(gòu)成被動(dòng)關(guān)系，故應(yīng)用 be done形式。故選Do【點(diǎn)睛】情態(tài)動(dòng)詞+have done的結(jié)構(gòu)和用法有以下幾種：一、must have done sth. 一定做了某事”。表示對(duì)過去事情的較有把握的推測(cè)，這時(shí)只能用 在肯定句中，肯定/必須已經(jīng)干過 ；在否定句和疑問句中用can'或couldn '或can/could,例如：1.From what you said, she must have told you all about it.從你的話看，她一定告訴了你所有 的

3、事情。二、can/could have done sth.本來能夠做某事，而實(shí)際上未做；1.But we could have done it all so much better.但是，我們本可以把這一切做得更好。三、can't/couldn't have done sth.不可能做過某事；1. We could't have done it without you.沒有你我們辦不成這事。四、ought to/should have done sth.過去本應(yīng)該做某事而實(shí)際上并沒有做。You should have done it when you first saw

4、 them blooming this spring. 你應(yīng)該在今年春天第 次看到它們盛開的時(shí)候就挖一些的。2.Even if it ' s something you should have done earlier in the oremissed a detail on.甚至你在一個(gè)星期前的就提早完成了一件事或者忽略了一個(gè)小細(xì)節(jié)。2. I don ' t really like Janes. Why did you invite him?-Don' t worry. He_come. He said he was ' t certain what his

5、plans were.A. must notB. need notC. would notD. might not【答案】D 【解析】考察情態(tài)動(dòng)詞，題干中的he wasn' t certain說明他可能不來，可能來，因此使用不完全否定，might not。3. - Oh, my God! I just missed the last bus back home.- That s really bad. I m sure you it, but you just didn t hurry up.A had caughtB could have caught C could catchD

6、can catch【答案】B【解析】【詳解】考查情態(tài)動(dòng)詞+have done 結(jié)構(gòu)。句意： 哦 ,我的上帝!我剛好錯(cuò)過了回家的末班車。這是非常糟糕的。我肯定你能趕上，但你就是不抓緊。could have done 本能做“來而沒有做 ”。故選B。4. - Did Jim come?- I don t know. He while I was out.A might have comeB might comeC must have comeD should have come【答案】A【解析】【詳解】考查情態(tài)動(dòng)詞推測(cè)用法。句意：Jim 來了嗎？-我不知道，在我不在的時(shí)候，可能來過。根據(jù)前文I d

7、on ' t know.知，說話者不知道Jim來沒來，因此后文推測(cè)來過，但是語氣很不確定，故可知選 A。對(duì)過去情況的推測(cè)為情態(tài)動(dòng)詞+have done , must have done 一定做了某事， should have done 應(yīng)該來過，不符合，故選A。【點(diǎn)睛】情態(tài)動(dòng)詞+have+過去分詞的用法，表示推測(cè)或判斷過去的情況。can/could+have+過去分詞用法： 多用于否定句和疑問句中。表示對(duì)過去某事發(fā)生的可能性的否定或質(zhì)疑，意為：不可能（已經(jīng)）了 -（否定句）/可能（已經(jīng)）了嘛？ -（疑問句） 用于肯定句中。表示對(duì)過去沒有做某事的遺憾，含有輕微的責(zé)備，意為：本來可以 的（

8、但實(shí)際上沒有）。 You could have done better, but you were too careless. （肯定句。他能做得更好的）should/ought to+have+ 過去分詞用法：用于肯定句中。表示對(duì)過去沒有做某事的遺憾，含有責(zé)備的意思，意為：本來應(yīng)該的（但實(shí)際上沒有）。用于否定句中-表示對(duì)過去已經(jīng)做了某事的責(zé)備，意為：本來不應(yīng)該的（但實(shí)際上已經(jīng)了）。 He should have beenasleep.（肯定句，他本應(yīng)去睡覺的） He shouldn't have been asleep.（否定句，他本來不應(yīng)該 去睡覺的）。may/might+have

9、+ 過去分詞用法：用于肯定句和否定句中，表示對(duì)過去發(fā)生某事的可能性的推測(cè)，意為：或許（已經(jīng)）/或許還沒有。 It is too late. He may have gone to bed.must+have+過去分詞用法：表示對(duì)過去發(fā)生的事情十分肯定的推測(cè)。must表示推測(cè)時(shí)，不能用在否定句和疑問句中。I must have forgotten to tell you. （ must 的引入，表達(dá)了說話者對(duì) 過去忘記告訴你的這件事肯定推測(cè)）needn't+have+ 過去分詞用法：表示對(duì)過去已經(jīng)做了某事的后悔，意為：本來可以不必的（可實(shí)際上卻已經(jīng) ） You needn't h

10、ave taken a taxi here, for it was very near to my home.5. The accident which left 15 people on board dead if both the angry femalepassenger and the bus driver had kept calm.A should have avoidedB should be avoidedC could have avoidedD could have been avoided【答案】D【解析】【詳解】考查 “情態(tài)動(dòng)詞+完成式”。句意：如果憤怒的女乘客和巴士司

11、機(jī)保持冷靜，這起導(dǎo)致15 人死亡的事故本來是可以避免的。could have done 本來能做而“沒有做 ”，且句子主語Theaccident 和謂語動(dòng)詞avoid 之間是被動(dòng)關(guān)系，結(jié)合句意可知答案為D?！军c(diǎn)睛】情態(tài)動(dòng)詞+ have done 結(jié)構(gòu)：1. “must + have+去分詞”表示對(duì)過去發(fā)生的事情或狀態(tài)進(jìn)行推測(cè)，語氣比較堅(jiān)定，通常只 用于肯定句。如：It must have rained last night,for the ground is wet.2. “ can / could + havei+去分詞”表示對(duì)過去某種情況的懷疑或不確定。can和could 一般用于否定句和

12、疑問句，could 的語氣較can 弱。如：He can't have finished the work so soon.3. may / might + have過去分詞”表示對(duì)已發(fā)生的動(dòng)作或存在的狀態(tài)進(jìn)行不肯定的推測(cè)， might 的語氣比may 弱一點(diǎn)。這種結(jié)構(gòu)主要用于肯定句和否定句，疑問句改用can 或could。 如： They may not have known it beforehand.4. “need + have+去分詞”表示過去做了不必做或不需要做的事情，或過去做某事純屬多 余。如：I needn't have bought so much wine

13、only five people came.5. “ should / ought to + have +過去分詞”表示過去本該做某事但沒做，其否定式表示過去不該做某事但做了，這種句式含有不滿或責(zé)備之意，ought to 的語氣比should 強(qiáng)一些。如：You ought to / should have studied harder. 你本應(yīng)該更努力學(xué)習(xí)的.（但沒有）He oughtn't to / shouldn't have done that. 他本來就不該做那件事.（可是做了）6. “ would have 過去分詞”表示對(duì)過去的某種情況進(jìn)行猜測(cè)，或本來要做某事卻因

14、某種原因未做成，通常用來說明某一情況，但不像用should 或 ought to 那樣含有責(zé)備之意。如：I guess the poet would have been about twenty when she wrote her first poem. Another worker wouldn't have acted like that.6. The room is so clean. He have cleaned it yesterday evening.A willB needC canD must【答案】D【解析】【詳解】考查情態(tài)動(dòng)詞表推測(cè)。句意：房間如此干凈，他一定是

15、昨天晚上打掃過了。must have done表示對(duì)過去發(fā)生的事情有把握的猜測(cè)，意思是“一定(做過)”，故 D 項(xiàng)正確。7. Mum, little Ray broke his toys again!It doesn't matter. You see, accidents happen.A shallB shouldC mustD will【答案】D【解析】【詳解】考查情態(tài)動(dòng)詞辨析。句意： 媽媽，小雷又弄壞了他的玩具。 沒事的，你看，意外總會(huì)發(fā)生。A. shall將要，會(huì)；B. should應(yīng)當(dāng)；C. must必須；D. will總是。Will可以表示習(xí)慣，意思為“慣于，總是”。故

16、D 選項(xiàng)正確?！军c(diǎn)睛】will/would 是情態(tài)動(dòng)詞，其表達(dá)的意思如下。(1)表示意志或意愿：決心，愿意，好嗎？We will do our best to save the child. 我們會(huì)盡力搶救這個(gè)孩子。I told her to stop crying, but she just wouldn我叫她別哭，可她就是不愿聽。 t listen.注：表示請(qǐng)求、建議或征求對(duì)方意見時(shí)，用 Would you - ?比用 Will you 里婉轉(zhuǎn)。如：Will/Would you please keep the door open？ 請(qǐng)讓門開著好嗎？Will/Would you go wit

17、h me? 你愿意和我一起去嗎?(2)表示真理或習(xí)慣：慣于，總是。如：Oil will float on water. 油總是浮在水面上。She will listen to music alone in her room for hours. 她獨(dú)自在房間里聽音樂，一聽往往就是幾小時(shí)。He would get up early when he lived in the country. 他住在鄉(xiāng)下時(shí)總是早起。(3)表示要求：一定，必須。如：You will report to me afterward. 你稍后一定要向我報(bào)告。(4)表示猜測(cè)：可能，大概。如：This will be the

18、house you' re looking for是你找的那所房子了。(5)表示功能：能。如：This auditorium will/would seat one thousand people. 這個(gè)禮堂能容納一千人分析句子可知，本句中的will 表示習(xí)慣，意思為“慣于，總是”且符合語境。故D 選項(xiàng)正確。Life is like8. I often felt troubled in my teens and my grandma comfort me, sayingthat, dear ”.A wouldB mightC shouldD must【答案】A【解析】【詳解】考查情態(tài)動(dòng)

19、詞。句意：在我十幾歲的時(shí)候，我經(jīng)常感到煩惱，我的奶奶會(huì)安慰我說，“生活就是這樣，親愛的”。此處是would+ 動(dòng)詞原形，表示“過去總是做某事”。故選A。9. What s wrognwith you?Oh, I am sick. I so much ice cream just now.A shouldn t eatB mustn t eatC couldn t have eatenD shouldn t have eaten【答案】D【解析】【詳解】考查情態(tài)動(dòng)詞和虛擬語氣。句意： 你怎么了？ 我生病了，我剛才不應(yīng)該吃那么多冰激凌。A. shouldn ' t eat應(yīng)該吃；B. mu

20、stn ' t eO止吃；C. couldn ' t havaten 不可能 吃；D. shouldn ' t have eaten來不應(yīng)該吃。根據(jù) just now可知，是發(fā)生在過去，故選 D。10. Can I pay the bill by check? Sorry， sir But it is the management rules of our hotel that payment be made incashA shallB needC willD can【答案】A【解析】【詳解】考察情態(tài)動(dòng)詞用法。句意： 我能用支票付賬嗎?對(duì)不起,先生。但這是我們酒店的管

21、理規(guī)定,支付要用現(xiàn)金。shall 可以表示命令，警告，強(qiáng)制，或者指規(guī)則和法律要求做的事情。本題正是考察了 shall表示按照規(guī)則和法律要求做的事情。故 A正確。11. -Artistic people can be very difficult sometimes.-Well, youknow-you married one.A mightB wouldC shallD should【答案】D【解析】【詳解】考查情態(tài)動(dòng)詞詞義辨析。A. might可能，也許；B. would將會(huì)；C. shall必須，會(huì)；D. should應(yīng)該。句意：-有藝術(shù)修養(yǎng)的人有時(shí)很難相處。-你應(yīng)當(dāng)知道這一點(diǎn)，因?yàn)槟憬Y(jié)婚

22、那位就是搞藝術(shù)的。這里是按照常理推斷，用should。12. I feel a little nervous. Take it easy. You have difficulty passing the exam when you have prepared for itwell.A. mustn ' tB. needn ' tC. may notD. shouldn ' t【答案】D【解析】【詳解】考查情態(tài)動(dòng)詞。句意：我覺得有點(diǎn)緊張。一一不要著急。當(dāng)你準(zhǔn)備充分時(shí)，通過考試應(yīng)該不會(huì)有困難。 A. mustn '禁止，不允許；B. needn '不必s C

23、. may not可能不會(huì)；D.shouldn '不應(yīng)該。結(jié)合句意可知答案為D。13. 一 you disturb me now? I ' m busy preparing a report.-Terribly sorry, but I have something urgent to tell you.A. NeedB. ShouldC. MightD. Must【答案】D 【解析】 【詳解】考查情態(tài)動(dòng)詞特殊用法。句意：一你非要現(xiàn)在打擾我嗎？我正在準(zhǔn)備一份報(bào)告。一真對(duì)不起，但是我怕有緊急事情告訴你。A. Need需要；B. Should應(yīng)該；C. Might也許；D. Mus

24、t必須；一定；偏偏，非得；根據(jù)語境可知must表示編偏，非得”符合上下文語境，用來指責(zé)對(duì)方。故D項(xiàng)正確。14. It ' s already 11 o k , anddioc have been here half an hour ago.Maybe he got caught in the rain.A. mustB. ought toC. mayD. can【答案】B【解析】【詳解】考查情態(tài)動(dòng)詞。句意：已經(jīng) 11點(diǎn)了，他半小時(shí)前就該到了。A. must have done必定做了（表示對(duì)過去的推測(cè)）； B. ought to have done本應(yīng)該做的；C. may have d

25、one可能已經(jīng)做過某事；D. can have done本來可以做的（但沒有做），根據(jù)題意，故選B。15. - Difficulties always go with me!-Cheer up! If God closes door in front of you, there be a window opened for you.A. mustB. wouldC. couldD. can【答案】A【解析】【詳解】考查情態(tài)動(dòng)詞辨析。句意：困難總是伴隨著我！一一高興點(diǎn)！如果上帝在你面前關(guān)上了門，一定有一扇窗戶為你打開。A. must必須；B. would將要；C. could能，會(huì)；D. can

26、能，會(huì)。must表示對(duì)現(xiàn)在的狀態(tài)推測(cè)時(shí)，意為定”，表示可能性很大的推測(cè)。符合語境。故選Ao【點(diǎn)睛】1) must用在肯定句中表示較有把握的推測(cè)，意為 “一定"。2) must表對(duì)現(xiàn)在的狀態(tài)或現(xiàn)在正發(fā)生的事情的推測(cè)時(shí)，must后面通常接系動(dòng)詞 be的原形或行為動(dòng)詞的進(jìn)行式。3) must表示對(duì)已發(fā)生的事情的推測(cè)時(shí)，must要接完成式。4) must表示對(duì)過去某時(shí)正發(fā)生的事情的推測(cè)，must后面要接完成進(jìn)行式。5)否定推測(cè)用can't。本句中的。must表示對(duì)現(xiàn)在的狀態(tài)推測(cè)時(shí)，意為一定，表示可能性很大的推測(cè)。符合第 2 點(diǎn)用法。16. According to a newly r

27、eleased regulation on online video services, no one generate,release or spread fake news or information by using such technologies.A. canB. shallC. willD. may【答案】B 【解析】 【詳解】考查情態(tài)動(dòng)詞。句意：根據(jù)最新發(fā)行的關(guān)于網(wǎng)絡(luò)視頻服務(wù)的規(guī)章，任何人都不可以使用此類技術(shù)生成、發(fā)行或者傳播虛假消息。A. can能夠，有時(shí)會(huì)；B. shall三人稱表示征求對(duì)方意見；二三人稱陳述句，表示允諾、威脅、恐嚇或法律條文的規(guī)定。C. will意愿；D

28、.may也許，可能。根據(jù)前面的 regulation (規(guī)定)可知，本題選 shall更加合理。故選 B。17. AI will surely be a feature of future life, but it be used responsibly and in a proper way.A. canB. needC. mustD. will【答案】C【解析】 【詳解】考查情態(tài)動(dòng)詞。句意：人工智能肯定會(huì)成為未來生活的一個(gè)特征，但必須以負(fù)責(zé)任的方式和適當(dāng)?shù)姆绞绞褂盟. can能夠；B. need需要；C. must必須；D. will將會(huì)。此處為情態(tài)動(dòng)詞的一般用法，結(jié)合句意表示 必須&

29、quot;，故選Co18. You be right but I ' m going back to check anyway.A shouldB mustC needD might【答案】D【解析】【詳解】考查情態(tài)動(dòng)詞。句意：你或許是對(duì)的，但我還是要回去核對(duì)一下。A. should 應(yīng)該； B. must一定，必須；C. need 需要； D. might 或許。本題主要考查情態(tài)動(dòng)詞表示推測(cè)的用法，由I going back to check anyway 可知，我對(duì)此不確定。由此可知，D 項(xiàng)符合題意。故選D 項(xiàng)?！军c(diǎn)睛】can / could 用于表推測(cè)的用法（1） 從使用句型上看

30、，can 通常只用于否定句或疑問句，一般不用于肯定句，而could 可用于肯定句、否定句和疑問句。兩者沒有時(shí)間上的差別，只是could 比 can 更委婉，更不確定。（2） 從時(shí)間關(guān)系看，對(duì)現(xiàn)在或?qū)砬闆r作推測(cè)，后接動(dòng)詞原形；對(duì)正在進(jìn)行的情況作推測(cè)，后接be doing 結(jié)構(gòu)；對(duì)過去情況作推測(cè)，后接動(dòng)詞完成式。2、 may / might 用于表推測(cè)的用法表示推測(cè)，兩者都可用，只是 might比may語氣更不確定，表示的可能性更小。如本題，根據(jù)I' m going back to check anyway"知，我對(duì)此不確定。由此可知，D項(xiàng)符合題意。（1）在句型使用方面：兩者均

31、可用于肯定句和否定句，但用于疑問句時(shí)，may 通常不用于句首，但可用于疑問句的句中（如特殊疑問句等），而might 盡管可以用于疑問句的句首，但不算普通，通常會(huì)改用其他句式（如用could 等）。3、 must 表示推測(cè)的用法must 表示很有把握的推測(cè)，其意為“一定會(huì) ”“ 肯定會(huì) ”，只用于肯定句，一般不用于否定句或疑問句。表示對(duì)現(xiàn)在或未來的情況作推測(cè)，后接動(dòng)詞原形；表示對(duì)過去情況的推測(cè)，接動(dòng)詞完成式。19 - I called you last night, but no one answered.- Sorry, I sleeping.A must have doneB would h

32、ave beenC must beD could be【答案】C【解析】【詳解】考查情態(tài)動(dòng)詞。句意： 昨晚我給你打電話了，但沒人接。 對(duì)不起，我一定是睡著了。分析可知，前文提及打電話無人應(yīng)答，后文解釋原因：肯定睡著了。情態(tài)動(dòng)詞must 可用于must be+v-ing表示 過去肯定在做某事”，符合句意要求。故選 C項(xiàng)。20 - Catherine, I have cleaned the room for you.-Thanks. You it. I could manage it myself.A. needn ' t do B. shouldn ' t haVone C. m

33、ustn ' t do D. needn ' t have done 【答案】D 【解析】 【詳解】考查情態(tài)動(dòng)詞辨析。句意：一凱瑟琳，我已經(jīng)為你打掃了房間。-謝謝。你本不必這么做的。我自己能行。 A. needn ' t d不必做某事；B. shouldn ' t have done不應(yīng)該做某事；C.mustn' t d禁止做某事；D. needn ' t have done不必做某事。由 "Thanks. I could manage itmyself可知，needn' t have done本不必做某事，而實(shí)際上做了某事”符

34、合句意。故選 D項(xiàng)。21. I heard they went skiing in the mountains last winter.It _ true because there was little snow there.A. may be notB. won' t beC. couldn ' t be D. mustn' t be【答案】C【解析】【詳解】考查情態(tài)動(dòng)詞辨析。句意：我聽說他們?nèi)ツ甓烊ド嚼锘?不可能是真的，因?yàn)槟抢飵缀鯖]有雪。A. may be not 可能不；B. won ' t b不會(huì)；C. couldn ' tbM能是；D

35、. mustn ' tbe禁止。根據(jù) because there was little snow there.可知這里是否定推測(cè)，couldn ' t be可能是"符合句意，故選C項(xiàng)。22. I my examination easily but I made too many stupid mistakes.A. should passB. could have passedC. had passedD. must have passed【答案】B 【解析】【詳解】考查情態(tài)動(dòng)詞+have done的用法。句意為：我本來能夠輕松地通過這次考試的，但是我犯了 太多愚蠢的

36、錯(cuò)誤。結(jié)合語境可知，此處考查虛擬語氣，且與過去的事實(shí)相反，應(yīng)用could/would/might have done 的結(jié)構(gòu)，could have passed本能通過（事實(shí)上未通過），故選B項(xiàng)。【點(diǎn)睛】本題考查情態(tài)動(dòng)詞的過去式+have done的虛擬語氣的用法，常見結(jié)構(gòu)有should/shouldn ' thave done; could/couldn't have done/ would/wouldn't have done/ need/ needn't have done/Without your help, I couldnIt cleared up,

37、 I neednmight have done例如：'t have passes如thetes你的幫助，我本不能通過測(cè)試。't have brought the umbrep/,我本沒有必要帶傘的。23 Isn t thAatnn s husband over there? No, it be him I m sure he doesn t wear glasses.A must notB can tC wontD may not【答案】B【解析】【詳解】考查情態(tài)動(dòng)詞：句意：那不是安的丈夫嗎？-不，肯定不是他，我確定他不戴眼鏡。A.must not禁止；B. can不能;C.

38、won不會(huì);D. may not可能不。表示否定的推測(cè)，不可能，用 can t 。故選 B 項(xiàng)。24 Are you going on a holiday after the exam? Well, I haven t decided yet. I find some other choices.A wouldB mightC mustD should【答案】B【解析】【詳解】考查情態(tài)動(dòng)詞辨析。句意： 考試后你要去度假嗎?嗯，我還沒有決定。我可能會(huì)發(fā)現(xiàn)一些其他的選擇。A. would 將會(huì)； B. might 可能； C. must 必須； D. should 應(yīng)該。根據(jù)上文“I haven&

39、#39;t decided yet可推斷，我可能還有別的選擇，表示可能性，might符合語境，故選B。25 Skills like critical thinking and analysis be found on the Internet, because theymust be acquired in the context of facts.A can tB needn tC mustn tD shouldn t【答案】A【解析】【詳解】考查情態(tài)動(dòng)詞詞義辨析。句意：像批判性思維和分析這樣的能力，是不能在互聯(lián)網(wǎng)上找到的，因?yàn)樗鼈儽仨毣谑聦?shí)來獲得。A. can t 無法，不可能；B. n

40、eedn t 不需要；C. mustn t不可以，禁止；D. shouldn t 不應(yīng)該。本題講的是這種批判性思維的能力無法通過瀏覽魚龍混雜的網(wǎng)上信息獲得，表達(dá)的是客觀上的不可能，故選A。26 He his stay in France, didn't he? He looks amazingly different.A will have enjoyedB should have enjoyedC can have enjoyedD must have enjoyed【答案】D【解析】【詳解】考查情態(tài)動(dòng)詞+have done。句意：他在法國(guó)一定過得很愉快，是嗎？他看起來很不一樣。mu

41、st have done 一定做某事。表示對(duì)過去事情的較有把握的推測(cè)。由“ He looks amazinglydifferent. 可知，他在法國(guó)一定過得很愉快。所以這是對(duì)過去事情的較有把握的推測(cè)。故選 ” D 項(xiàng)。27 We have watered these flowers yesterday. Today s rain will be too much for them.A can tB shouldn tC may notD mustn t【答案】B【解析】【詳解】考查情態(tài)動(dòng)詞。句意：我們昨天不應(yīng)該給這些花澆水。今天的雨對(duì)他們來說太大了。A.can'不可能；B. shoul

42、dn 不應(yīng)該；C. may not或許不會(huì)；D. mustn '禁止，不允許。情態(tài)動(dòng)詞的完成時(shí) should' t have done不應(yīng)該做而做了 "。根據(jù) Today' s rain will be too much forthem. 可知，此處指昨天不應(yīng)該給這些花澆水。故選B?！军c(diǎn)睛】情態(tài)動(dòng)詞+ have done 結(jié)構(gòu)：1. “must + have過去分詞”表示對(duì)過去發(fā)生的事情或狀態(tài)進(jìn)行推測(cè)，語氣比較堅(jiān)定，通常只 用于肯定句。如：It must have rained last night, for the ground is wet.2. &quo

43、t; can / could + haveM去分詞”表示對(duì)過去某種情況的懷疑或不確定。can和could 一般用于否定句和疑問句，could 的語氣較can 弱。如：He can't have finished the work so soon.3. may / might + have過去分詞”表示對(duì)已發(fā)生的動(dòng)作或存在的狀態(tài)進(jìn)行不肯定的推測(cè),might的語氣比may弱一點(diǎn).這種結(jié)構(gòu)主要用于肯定句和否定句，疑問句改用 can或could, 如： They may not have known it beforehand.4. “need + have+去分詞”表示過去做了不必做或不需要做的事情，或過去做某事純屬多余，如：I needn't have bought so much wi