情態(tài)動詞表推測用法總結及專項練習

1、情態(tài)動詞表推測用法總結及專項練習1.can / could用于表推測的用法(1) 從使用句型上看， 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。兩者沒有時間上的差別，只是 could 比 can 更委婉，更不確定。如：It can t couldnt be true.那不可能是真的。What can could they be doing?他們會在干什么呢 ?We could go there this summer.今年夏天我們可能要去那兒。注：can 有時也用于肯定句中表示推測，主要用于表示理論上的可能性 ( 即從理論上看是可能的，但實

2、際未必會發(fā)生) ，或表示“有時”之意。如：Even experienced teachers can make mistakes.即使是有經驗的教師也可能出錯。She can be very unpleasant.她有時很令人討厭。(2) 從時間關系看，對現在或將來情況作推測，后接動詞原形；對正在進行的情況作推測， 后接 be doing 結構；對過去情況作推測，后接動詞完成式。如：He could have gone home.他可能已經回家了。He cant couldnt have understood.他不可能理解了。Why does he know this? Can Could s

3、omeone have told himabout it?他怎么知道 ? 會是哪個人告訴他了嗎 ?(3) “could+ 完成式”除表示對過去的推測外，還有以下重要用法： 表示過去沒有實現的可能性，常譯為“本來可以”。如：I could have lent you the moneyWhy didn t you ask me?我本來可以借這筆錢給你的。你為什么不向我提出? 用來委婉地責備某人過去應該做某事而沒有去做，常譯為“本來應該”。如：You could have helped him.你本來應該幫助他的。 表示“差點兒就要”。如：I could have died laughing.我差

4、點兒笑死了。2. may / might用于表推測的用法表示推測，兩者都可用，只是 might 比 may 語氣更不確定，表示的可能性更小。(1) 在句型使用方面：兩者均可用于肯定句和否定句，但用于疑問句時， 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，通常會改用其他句式（如用 could 等）。如：He may might know the answer.他可能知道答案。He may might not believe you.他可能不會相信你。And who may might she be?那么她會是哪一位呢？(2)

5、 從時間關系看，對現在或將來情況作推測，后接動詞原形；對正在進行的情況作推測， 后接 be doing 結構；對過去情況作推測，后接動詞完成式。如：He may might tell his wife.他也許會告訴他妻子。He may might be writing a letter.他可能在寫信。She may might have read it in the papers.她可能在報上已讀到過此事。(3) “might+ 完成式”除表示對過去的推測外，還有以下重要用法： 表示過去某事可能發(fā)生而實際上卻并沒發(fā)生。如：It was really very dangerous. I migh

6、t have killed myself.那真的是太危險了，我差點沒命了。A lot of men died who might have been saved很多人本來可以獲救的卻死了。 表示委婉的批評或責備。如：You might have made greater progress.你的進步本來可更大一些的。You might at least have answered my letter.你至少可以回我一封信嘛。3. must 表示推測的用法must 表示很有把握的推測，其意為“一定會”“肯定會”，只用于肯定句，一般不用于否定句或疑問句。表示對現在或未來的情況作推測，后接動詞原形；

7、表示對過去情況的推測， 接動詞完成式。 如：I must be the happiest woman on earth!我一定是世界上最幸福的女人了。No, he must be lying.不，他一定在撒謊He must have mistaken my meaning.他一定誤會了我的意思。4. should have done的用法should have done 只用于談論過去情況，主要有兩個用法：一是用于推測過去已經發(fā)生的情況， 二是用于指本該發(fā)生而實際上未發(fā)生的情況。如：You should have told me so before.你早就應該告訴我。He should hav

8、e arrived by now.此時他本該到了。Look at the time! We should have been at the theatre tenminutes ago.瞧都什么時候了 !十分鐘前我們就該到戲院了。5. need have done的用法need have done 結構主要用于否定句或疑問句，一般不用于肯定句。用于否定句時，表示本來不必做某事，但實際上卻做了；用于疑問句時，用于詢問某一過去動作的必要性。如：You neednt have hurried.你當時實在不必那么匆忙。She neednt have comein person a letterwoul

9、d have beenenough. 她本不必親自來寫封信來就足夠了。Need you have paid so much?你當時真須要付那么多錢嗎?Need they have sold the farm?他們那時非得把農場賣掉不可嗎?歷屆 NMET中表推測的情態(tài)動詞的用法情態(tài)動詞是中學英語學習中的一個重點和難點， 也是高考的重點考察內容之一。其中表示推測用法的情態(tài)動詞在近幾年的高考中更是屢見不鮮?，F結合近幾年的高考題目， 對表推測的情態(tài)動詞的用法作一歸納，希望對各位考生會有所幫助：【考例】 1. Naturally,afterI toldher what todo, my daughter

10、_ go and do the opposite!A. may B. can C. must D. should(2003 年普通高等學校春季招生統一招生考試英語試題（安徽卷）)【分析】 Can,may,must 都可用來表示”推測”，但側重點各有不同：May常用來指”事實上的可能性”，而 can 則表示一種”理論上的可能性”例如：The railways may be improved.=It is possible that the railways will be improved.=Perhaps/Maybe/Possibly the railways will be improved

11、.鐵路可能會得到改進。（意味著已有具體的改進計劃或方案。）The railways can be improved.=It ispossible for the railwaysto be improved.鐵路可以得到改進。（意思是鐵路還不完善，尚有問題存在。）理論上的可能性 (can) 比事實上的可能性 (may) 更弱。在一般的陳述句， can 與 sometimes 幾乎相同，表示一種偶然的可能性。比如：Even expert drivers can make mistakes.甚至是很熟練的駕駛員也可能會犯錯。=Even expert drivers sometimes make m

12、istakes.=It is possible for the expert drivers to make mistakes.因此，如果講的是一種特殊情況，不是一般情況，就用may,試比較：Mr Reed looks pale.He may be ill.Mr Reed is in poor health.He can be ill at any time.Must 指邏輯必然 , 作“想必”、“準是”、“一定”解，用來表示我們對某事有把握的推論或揣測。 （考慮到跡象如此， 再無別的結論 =Itseems certain that. ） :They must be very tired no

13、w, for they have been working thewhole morning.他們現在一定是非常累了，因為他們整個上午都在工作。析：填C.must。意思是”不出所料，當我告訴女兒要做的事時，她準會去做相反的事?！薄究祭?1、 Mary _ be in Paris.I saw her in town only a fewminutes ago.(NMET1994)A.mustnt B.shouldnt C.can tD.may not2 、.-Is John coming by train? (NMET 2002 Tianjing )-He should,but he _ no

14、t.He likes driving hiscar.Amust B.can C.need D.may【分析】 May用于否定時， not 不是否定 may，而是否定句中的動詞，這一點與 can 不同，試比較：He may not know the truth.他可能不知道事情的真相。（=It ispossible that he didnt know the truth.）He cannot know the truth.他不可能知道事情的真相。must 表示推測的這種用法通常用在肯定句中，在疑問句中常用can( 可能 ) ，在否定句中常用cant( 不可能，不會是) ，而不用mustnt 。

15、例如：- Somebody is knocking at the door. Who can it be ? It must be Wang Hong.- No, It can t be Wang Hong, because she left for Shanghaithis morning.- 有人在敲門。會是誰呢？一定是王紅。- 不，不會是王紅，因為她今天早晨就動身去上海了。因而 You must be joking.在意義上相當于You cant be serious.析： 1、填 C。意思是”瑪麗不可能在巴黎。幾分鐘前我還看見她在鎮(zhèn)上。 2、填 D。意思是” - 約翰會坐火車來嗎？ -

16、 應該會，但他可能不會。他喜歡開車?！薄究祭?1.-I heard they went skiing in the mountains last winter. (NMET 2002Beijing )-It _ true because there was little snow there.A.may not be B.won't be C.couldn't beD.mustn't be【分析】 Could,might表示過去的可能性。I thought it might be true.我本認為那是真的。He could be very unreasonable.

17、他有時可能毫不講理。析：填 C。它是對去年冬天所發(fā)生的事進行評價。【考例】 1.- Are you coming to Jeffs party? (NMET 2000)- I m not sure.I_go to the concert instead.A.must B.wouldC.shouldD.might2.-Look!The clouds are gathering.-Yes.I'm afraid it _ be pouring down soon.A,can B,must C,should D,might【分析】 could 和 might 表示現在的情況時，更帶有不肯定性和

18、慎重味道，構成禮貌或婉轉說法，包含或許的意思：A:Iwonder where Tom is.B:He may/might/couldbe inthelibrary.(Perhaps he is in the library.)因 此 在wonder,fear,beafraid等 后 接 的 從 句 中 , 通 常 用may/might/could,表達一種探詢的觀點：I was afraid you might be out of sorts.假設性的可能和試探性的可能，也用Ourteam mightstillwinthecould race.(我怕你可能心情不痛快。和 might ：可 以

19、意 譯 為 ： Itispossible,though unlikely,that)析： 1、 2 均填 D.might【考例】 Mr. Bush is on time for everything. How _ itbe thathe was latefortheopeningceremony?A canBshouldCmayDmust(2001 年上海普通高校春季招生考試試卷)【分析】表示推測的may通常不用于一般疑問句，而要用can 代替。Can用于一般疑問句時，還可表示驚訝或懷疑，意思是”（到底）可能有這樣的事嗎？”，比如：“There is the doorbell.” Whocan

20、 itbe at thistime of day?”有人按門鈴?！边@個時候到底會是誰呢？”Must 也偶爾用于疑問句： Must there be some good reason for thedelay?這個問句設想的是一個肯定的回答，可以解釋為”Does therehave to be some good reason ?”may可用于特殊疑問句或wh-從句，意思是”（到底）是”、”不知是否”：I wonder what it may mean.我不知道這究竟是什么意思。How old may his father be?他父親到底有多大年紀？（比How oldis his father

21、?委婉的說法。）析：填 1、A.can. （布什先生做什么事都很按時。他怎么可能會在開幕式上遲到呢？）【考例】 1. Sorry I'm late.I _ have turnedoffthe alarmclock and gone back to sleep again.( 2000年普通高等學校春季招生考試(北京、安徽卷 )A.mightB.shouldC.canD. will2. There were already fivepeople in the car but theymanaged to take me as well.It_A.can't beD.couldn&

22、#39;t have beena comfortable journey. (NMET95)B.shouldn't beC.mustn't have been【分析】“情態(tài)動詞have + -ed分詞”結構可以表示對已發(fā)生的事情進行推測 ,就表示的可能性程度而言， must 最大，could 其次，may更次之， might 最小。must + have + -ed分詞 :用于肯定句 ,表示推測過去某事“肯定,一定，準是”發(fā)生了。 其否定形式為：cant / couldn t have v-ed,表示過去不可能發(fā)生某事。may(might) + have + -ed分詞 :用于

23、肯定句和其他否定句,表示對已發(fā)生事情的不肯定的推測,意為“可能 ,大概” ,其中 might 較 may語氣更弱 ,把握更小。Can/could用于否定或疑問句中 , 表示對過去發(fā)生的事件的“懷疑或不肯定”。could比 can 更表示說話人語氣的不肯定。例如：I mailed that letter a week ago. He must have received it.我一周前就發(fā)出了那封信,想必他一定收到了。I cant findmy keys. I may / might have leftthem at the schoolyesterday.Jackcanthavearrived

24、yet,otherwisehewouldhavetelephoned me. （上海 1997）It couldn't have been Mr. Smith. He has gone to China.不太可能是史密斯先生。他已去了中國。另外，注意 may不可用于疑問句， 它的這種功能已為can 所取代。例如 Can they have missed the bus?的答句是：Yes,they may have done.而不是 Yes,they can have done.這一點要注意。Must 偶爾也能用于否定句： His absence must not have been n

25、oticed.此句和 His absence can t have been noticed.的意思是一樣的。許多評論者認為這類句子是不可能成立的，但它們正在為越我來越多的人所接受和使用，在美國英語中尤其如此。對正在發(fā)生的事情進行推測，則采用”情態(tài)動詞+be+現在分詞”結構，其中情態(tài)動詞的區(qū)別與上相同。析：答案 A、D。can 通常不用于肯定句表猜測；”should+have+ -ed分詞”表示”過去本來應該做”，但實際上沒有做， 意思是”本該 . ”，帶有責備口氣:I was really anxious about you.Youshouldn thaveleftwithoutaword.

26、(NMET2001) ；”will+have+ -ed 分詞”只是將來完成時的一種形式?！究祭?1.It's nearly seven o'clock. Jack _be here at anymoment. (NMET95)A.mustB.needC.shouldD.can【分析】 should(oughtto) 表示很可能、預期的意思，指一種嘗試性推論，可認為是 must 的語氣較弱的對應詞，意思是”應該會、一定。吧”。試比較：Our guests must be home by now.(I am certain) 我們的客人現在一定到家了。 （根據他們動身的時間、路程

27、遠近、速度等具體條件，我能斷定 / 肯定他們現在已經到家了。）Our guests should(ought to) be home by now.( They probably are,but I m not certain.) 我們的客人現在該到家了。（含義是我想他們很可能到家了，但我不能肯定”）與 must 不同還在于它常常表示將來：-When can I come forthe photos?Ineed them tomorrow afternoon.-They_bereadyby12:00.(NMET1998) A.canB.shouldC.might D.need表示不太可能可用s

28、houldn t(oughtn t to):There shouldn t(oughtn t to) be any difficulties.不該有任何困難。析：填 C。意思是”將近七點了。杰克很可能隨時會到?！?另外，在近幾年的 NMET中，對情態(tài)動詞及其它語法項目的考查均放到一定的語境中進行，要求考生利用所學英語各項基礎知識進行初步的語言運用，而不再是單純的語法知識題和短語題。這類試題往往通過題干的其他部分或附加句子提供某個信息，然后讓考生根據這個信息進行合理推理，產生新的想法和認識。因此，在做這類題時，除要熟悉所考查的語法規(guī)則外， 還要認真分析句子的結構，注意抓住關鍵詞， 分析上下文的邏

29、輯關系。不能單憑語法規(guī)則做題。鞏固練習1.Michael _ be a policeman, for he's much too short.A. need't B. can't C. should D .may2.Johnny,you _ play with the knife. You _hurt youself.A.won't,can'tB.mustn't,mayC.shouldn't,mustD.cant't,shouldn't3.Peter _ come with us tonight,but taken he

30、isn't very sure yet.A.can B.may C.will D.must4.Put on more clothes.You _ be taken feeling cold with onlya shirt on. A.must B.can C.could D.would5.It's nearly seven o'clock.Jack _ be here at any moment.A.must B.need C.should D.can6.I didn't hear the phone.I _ asleep.A.must be B.must h

31、ave been C.should be D.should have been7.Jack _ yet,otherwise he would have telephoned me.A.mustn't have arrived B.shouldn't have arrived C.can't havearrived D.need not have arrived8.-there were alreadyfive people inthe car buttheymanagedto take me as well. -It _ a comfortable journey.A.

32、can't be B.shouldn't be C.mustn't have been D.couldn't havebeen9.He _you more help,even though he was very busy.A.might have given B.might give C.may have given D.may give10.YesterdayJanewaookedawayfromthediscussion.Otherwise,she_ somethingthe would regretlater.A.had said B.said C.mi

33、ght say D.might have said11.There was plenty of time.She _.A.mustn't have hurried B.needn't have hurried C.should have written it out D.couldn't have hurried12.Tom ought not to _ me your secret,but be meant no harm.A.have told B.tell C.be telling D.haven't told13.I told Sally how to

34、get there ,but perhaps I _ for her.A.had to wirteitout B.must havewrittenitout C.should havewritten it out D.ought to write it out14.If you had worked harder,you _.A.would succeed B.had succeeded C.should succeed D.would have succeeded15.-If he _,he _that food. -luckily he wsa sent to the hospital i

35、mmediately.A.was warned;would not take B.had been warrned;had not taken C.would be warned;had not taken D.would have been warned;had not taken16.-I stayed at a hotel while in New York. -Oh,did you?You _ with Barbara.A.couldhavestayedB.couldstayC.wouldstayD.musthavestayed17.SorryI'mlate.I_ have turnedoffthe alarm and gone backto sleep again.A.might B.should C.can D.will18.-Shall I tell John abou