高考情態(tài)動(dòng)詞講解

1、語(yǔ)法專題(三)情態(tài)動(dòng)詞考 點(diǎn) 歸 納考點(diǎn)一： 情態(tài)動(dòng)詞表示能力1表現(xiàn)在的或一般的能力：表示現(xiàn)在的或一般的能力用can或be able to，can比be able to使用得更普遍。can側(cè)重指有能力做某事；而be able to更強(qiáng)調(diào)通過(guò)努力、克服困難做成某事。A computer cant think for itself；it must be told what to do.He is a native speaker of English，so he can of course speak English quite well.2表示將來(lái)的能力：表示將來(lái)能力用will be able

2、to。If you have a good sleep，you will be able to work out this problem.如果你睡個(gè)好覺(jué)，你就能做出這道題。3表示過(guò)去的能力：could表示過(guò)去一般的能力，即不表示做或未做某事；而was (were) able to do則表示過(guò)去有能力并且成功地做了某事，相當(dāng)于managed to do something/succeeded in doing something?？键c(diǎn)二： 情態(tài)動(dòng)詞表示推測(cè)(可能性)可能性可分為客觀的(理論的)可能性和具體事情實(shí)際發(fā)生的可能性。1客觀的(理論的)可能性指并不涉及具體某事是否會(huì)發(fā)生，此種用法常常

3、可以說(shuō)明人或事物的特征。can用于肯定句中表示客觀的(理論的)可能性，can用于疑問(wèn)及否定句中則表示實(shí)際發(fā)生的可能性。The World Wide Web is sometimes jokingly called the World Wide Wait because it can be very slow.A leftluggage office is a place where bags can be left for a short time，especially in a railway station.2表示具體事情實(shí)際發(fā)生的可能性：表示具體事情實(shí)際發(fā)生的可能性的層次比較見(jiàn)下表(依次

4、遞減)：詞形肯定式否定式疑問(wèn)式must必定，必然 will大概；會(huì)不會(huì)should/oughttoshould/ought to表示根據(jù)常規(guī)、事理、經(jīng)驗(yàn)作出的對(duì)現(xiàn)在或未來(lái)比較有把握的判斷，意為“應(yīng)該，理應(yīng)”。can不可能有可能嗎？could可疑的可能不可能語(yǔ)氣比can弱may“或許，也許”；也未可知，也說(shuō)不定可能不；或許不might比may還弱比maynot還弱這些詞后接動(dòng)詞原形是對(duì)現(xiàn)在事情的推測(cè)，后接完成式則表示對(duì)過(guò)去事情的推測(cè)；其中can，may/might，should，ought to，must有時(shí)還可接進(jìn)行時(shí)表示對(duì)現(xiàn)在正在進(jìn)行的事情的推測(cè)。另外，can還可用于否定句、疑問(wèn)句或感嘆句中

5、，表示疑惑、驚訝或不相信等意思；而could既可用于肯定句又可用于否定句、疑問(wèn)句中；ought to和might表示推測(cè)時(shí)，并不一定表示過(guò)去，而表示可能性弱于他們相應(yīng)的現(xiàn)在時(shí)形式。She might not be in the company.She told me she would go to Shanghai.她可能不在公司，她告訴過(guò)我要去上海。Can he have gone to Wuhan?他有可能去武漢了嗎？What can he be doing at this moment?這時(shí)候他會(huì)在做什么？She cant be telling a lie.她不可能在說(shuō)謊。Your mo

6、ther may be waiting for you to return home.你媽媽可能正等著你回家呢。They must be following us just a little behind us.他們肯定在離我們不遠(yuǎn)處尾隨著我們。You should be doing your exercises instead of watching TV.現(xiàn)在你該做作業(yè)而不是看電視。考點(diǎn)三： 情態(tài)動(dòng)詞表示請(qǐng)求、允許、允諾1表示征求對(duì)方的意見(jiàn)或提出建議時(shí)，shall可以用于第一、第三人稱的疑問(wèn)句，will和would用于第二人稱的疑問(wèn)句。分別構(gòu)成：Shall I/we/he/she/they

7、.？或Will(Would)you(please).?Whats the name?Khulaifi.Shall I spell that for you?2could/would可以用于疑問(wèn)句表示請(qǐng)求，使語(yǔ)氣更加委婉，但其回答語(yǔ)不能再用could/would來(lái)回答。Could I borrow your dictionary?Yes，of course you can.3shall也可用于第二、第三人稱的肯定句和否定句中，表示說(shuō)話者命令、警告、允諾或威脅的語(yǔ)氣；shall也可用于第二、第三人稱表示法律、規(guī)定等。What does the sign over there read?“No pe

8、rson shall smoke or carry a lighted cigarette，cigar or pipe in this area.”4can和may都可表示許可，但can較隨便，may更正式。Can I use your computer?我用一下你的電腦可以嗎？May I have a look at your driving license please，sir?先生，我可以看一下你的駕照嗎？考點(diǎn)四： 情態(tài)動(dòng)詞表示必要性must常用來(lái)表示必要性，意為“必須”；should，ought to也可表示必要性，意為“(義務(wù)上)應(yīng)該”，在語(yǔ)氣上比must“必須”弱。表示現(xiàn)在或?qū)?lái)必

9、須做某事用“must動(dòng)詞原形”；表示現(xiàn)在或?qū)?lái)不必做某事時(shí)，用dont have to或neednt加動(dòng)詞原形；表示過(guò)去沒(méi)必要做某事時(shí)，分為兩種情況：當(dāng)表示過(guò)去沒(méi)必要做某事，但事實(shí)上卻做了，用neednt have done sth.；當(dāng)表示過(guò)去沒(méi)必要做某事，而不涉及是否做，可用didnt have to do或didnt need to do sth.或It was not necessary to do sth.等；如表示禁止，則要用mustnt或shouldnt，意為“不應(yīng)該”。The boss has given everyone a special holiday，so we nee

10、dnt go to work tomorrow.Johnny，you mustnt play with the knife；you may hurt yourself.考點(diǎn)五： 情態(tài)動(dòng)詞表示意愿will和would都可表示意志、意愿和決心；will還可表示現(xiàn)在的一種習(xí)慣、傾向或趨勢(shì)；而would則可表示過(guò)去反復(fù)發(fā)生的動(dòng)作或某種傾向；used to也表示“過(guò)去常?！?，但它暗含“現(xiàn)在不再”之意。I will never do it again.They asked us if we would do that again.Without water，fish will die.During the

11、 vacation，he would visit me every week.考點(diǎn)六： “情態(tài)動(dòng)詞have done”都表示對(duì)過(guò)去事情的推測(cè)或意愿。其具體用法見(jiàn)下表：情態(tài)動(dòng)詞完成式用法例句musthavedone表示對(duì)過(guò)去已經(jīng)發(fā)生的行為進(jìn)行推測(cè)，意為“想必/準(zhǔn)是/一定做了某事”。It must have rained last night for the road was quite muddy.canhavedone；cannothavedone表示對(duì)過(guò)去發(fā)生的行為的懷疑和不肯定，通常用在疑問(wèn)句和否定句中，意為“可能干過(guò)某事嗎？”；“不可能干過(guò)某事”。Can he have gone to

12、his aunts？He cannot have forgotten it.couldhavedone“已經(jīng)”之意，此外，還可以表示過(guò)去沒(méi)有實(shí)現(xiàn)的可能性，意為“本來(lái)可以”。I saw Mr.Wang just now.He couldnt have gone to Beijing.may/mighthavedone表示對(duì)過(guò)去已發(fā)生行為的推測(cè)，意為“也許/或許已經(jīng)(沒(méi)有)”。一般只用于肯定句或否定句中(在否定句中表示“可能不”)，不用于疑問(wèn)句。用might則表示語(yǔ)氣更加不肯定。Its too late.I think he may have gone to bed. He may not hav

13、e finished the work.She might have caught a cold.mighthavedone表示“本來(lái)可能”，但實(shí)際上沒(méi)有發(fā)生的事。另外，還可以表示“本來(lái)應(yīng)該或可以做某事”之意，含有輕微的責(zé)備語(yǔ)氣。You should not have swum in that sea.You might have been eaten by fish. You might have given him more help, though you were busy.should/oughtto havedone用于肯定句時(shí)，表示本該做某事，而實(shí)際上未做，意為“本應(yīng)該”；用于否

14、定句時(shí)，則表示不該做的事反而做了，意為“本不應(yīng)該”。You should have come to the meeting earlier. You ought to have done this exercise more carefully. You shouldnt have told her the truth. He ought not to have treated his parents like that.neednthavedone表示做了本來(lái)不必去做的事，意為“本沒(méi)必要做某事”；而didnt need to do則表示過(guò)去沒(méi)必要做而實(shí)際上也沒(méi)有做某事。You neednt

15、have taken a taxi here，for it was very near to my house. I didnt need to clean the windows.My brother did it.hadbetterhavedone用于事后的建議，含輕微責(zé)備的口吻，意為“當(dāng)時(shí)最好做了某事”，其否定式had better not have done表達(dá)相反的含義。You had better have started earlier. You had better not have scolded her.wouldratherhavedone表示“寧愿做過(guò)某事”，其否定式w

16、ould rather not have done表達(dá)相反的含義，兩者都表示“后悔”之意。I would rather have taken his advice. I raised objections at the meeting，but now I would rather not have done that.wouldlike/love tohavedone表示過(guò)去愿意做某事，但未做成，意為“愿意做過(guò)某事”。I would love to have gone to the party last night but I had to work extra hours to finish

17、 a report.考點(diǎn)七： 情態(tài)動(dòng)詞的其他用法1cannot butdo sth.相當(dāng)于have no choice but to do sth.或can not choose but do sth.，表示“不得不，只好”。2“may/might well動(dòng)詞原形”是一種常用結(jié)構(gòu)，意為“完全能，很可能”，相當(dāng)于to be very likely to。He may well be proud of his son.他大可為兒子感到自豪。Her appearance has changed so much that you may well not recognize her.她的模樣變化太大

18、，你很可能認(rèn)不出她了。3“may/might as well動(dòng)詞原形”意為“最好，滿可以，倒不如”，相當(dāng)于had better do sth.。You may as well do it at once.你最好馬上就做這件事。We may as well stay where we are.我們留在現(xiàn)在的地方倒也不錯(cuò)。cannot(或never等否定詞)與enough連用表示“再也不為過(guò)”。4may可以用于祈使句，表示祝愿。May we never forget each other.愿我們彼此永不相忘。May you return in safety.愿你平安歸來(lái)。5should可以用來(lái)表示

19、驚訝、失望等情緒，意思是“竟然；竟然會(huì)”。It seems so unfair this should happen to me.它發(fā)生在我身上似乎很不公平。6must表示“偏要、硬要”做某事，表示雖不情愿但也許可。How old are you，madam?If you must know.Im twice my sons age.7why/howshould結(jié)構(gòu)表示說(shuō)話人對(duì)某事不能理解、感到意外、驚異等意思，意為“竟會(huì)”。Why should you be so late today?你今天怎么來(lái)得這么晚？How should I know?我怎么會(huì)知道？8need和dare的用法need

20、和dare兩者既可用作情態(tài)動(dòng)詞也可用作行為動(dòng)詞。作行為動(dòng)詞時(shí)，有人稱和數(shù)的變化，可用于肯定句、否定句或疑問(wèn)句，構(gòu)成否定和疑問(wèn)句時(shí)要加助動(dòng)詞do，does，did；作情態(tài)動(dòng)詞時(shí)，沒(méi)有人稱和數(shù)的變化(dare的過(guò)去式是dared)，直接接動(dòng)詞原形，多用于否定句和疑問(wèn)句中，構(gòu)成否定句和疑問(wèn)句時(shí)不用加助動(dòng)詞。dare作行為動(dòng)詞用于否定句和疑問(wèn)句時(shí)，后面的to也可省略，dare還可用于條件句中；need作行為動(dòng)詞時(shí)，還可表示“需要”，后接動(dòng)名詞的主動(dòng)形式表示被動(dòng)含義。He neednt go now.He doesnt need to go now.He didnt dare(to)do that.He

21、 dared not do that.Your room needs cleaning.Your room needs to be cleaned.解 題 技 巧1.情態(tài)動(dòng)詞主要表示說(shuō)話人的語(yǔ)氣或情感，所以我們?cè)诮獯鸫祟愒囶}的時(shí)候，一定要注意說(shuō)話者的語(yǔ)氣，要結(jié)合具體的語(yǔ)境來(lái)分析和判斷?？?例I heard they went skiing in the mountains last winter.It _true because there was little snow there.A. may not beB. wont beC. couldnt be D. mustnt be答案與解析：

22、C本題考查情態(tài)動(dòng)詞表推測(cè)的用法。根據(jù)語(yǔ)境there was little snow there表明對(duì)方所說(shuō)的他們?nèi)ド嚼锘┻@件事是不可能的。在表示“不可能”時(shí)，cant的語(yǔ)氣比may not強(qiáng)，故選C項(xiàng)。2注意“情態(tài)動(dòng)詞havedone”的結(jié)構(gòu)，它是歷屆高考試題中的重點(diǎn)，所以我們一定要牢固地掌握不同情態(tài)動(dòng)詞用于此結(jié)構(gòu)所表達(dá)的不同含義。考,例Was he present at the meeting?He_not have attended it，for he was busy repairing his computer all the time.A. can B. mightC. shoul

23、d D. must答案與解析：A本題考查“情態(tài)動(dòng)詞havedone”表對(duì)過(guò)去推測(cè)的用法。根據(jù)語(yǔ)境he was busy repairing his computer all the time可推斷他不可能參加這次會(huì)議，表示“可能”用can或might，但can的可能性大于might。錯(cuò) 解 分 析1.同類詞語(yǔ)意義不清考例1I should have been there，but I_not find the time.A. would B. couldC. might D. should答案與解析：B分析題意可知第二個(gè)分句表示過(guò)去的某種能力，故本題選B項(xiàng)。錯(cuò)因分析：C項(xiàng)只表示語(yǔ)氣上的可能性，與

24、題意不符。考例2I often see lights in that empty house.Do you think I_report it to the police?A. should B. mayC. will D. can答案與解析：A句意：我經(jīng)?？吹侥亲辗孔永镉袩袅痢Ｄ阏J(rèn)為我應(yīng)該把這件事向警局報(bào)告嗎？should和will分別用于第一人稱和第二人稱疑問(wèn)句，表示征詢意見(jiàn)。錯(cuò)因分析：同類詞語(yǔ)用法不清楚。can/may用于疑問(wèn)句則表示請(qǐng)求允許。can多用于口語(yǔ)中，may較正式。2語(yǔ)境理解錯(cuò)誤考,例Is John coming by train?He should，but he_not.

25、He likes driving his car.A. must B. canC. need D. may答案與解析：Dcome，go，leave，start等趨向動(dòng)詞的進(jìn)行時(shí)表示將來(lái)時(shí)，所以答語(yǔ)是對(duì)這一將來(lái)動(dòng)作作出的推斷。may not“可能不，不一定”，根據(jù)He likes driving his car.可以看出John可能乘火車來(lái)，也可能自己開(kāi)車來(lái)。may not正好符合這一語(yǔ)境。must not“不準(zhǔn)”；can not“不可能”；need not“不必”。錯(cuò)因分析：語(yǔ)境理解錯(cuò)誤。容易錯(cuò)選B項(xiàng)，但can not表不可能?？?題 對(duì) 接.高考題1(2009四川)I dont care w

26、hat people think.Well, you _.Acould BwouldCshould Dmight答案與解析：C句意：我不在乎人們想什么。不對(duì)，你應(yīng)該在乎。根據(jù)語(yǔ)境，后半句中省略了一些與前句相同的內(nèi)容。該題目實(shí)際上考查了情態(tài)動(dòng)詞的用法。should用以表示義務(wù)或責(zé)任，如：You shouldnt drink and drive.你不應(yīng)該喝酒后開(kāi)車。2(2009北京)One of the few things you _ say about English people with certainty is that they talk a lot about the weather

27、.Aneed BmustCshould Dcan答案與解析：D句意：對(duì)英國(guó)人，你能確定的幾件事情之一就是他們經(jīng)常談?wù)撎鞖?。need需要；must必須；should應(yīng)該；can能夠，根據(jù)語(yǔ)境D項(xiàng)合適。3(2009安徽)Some people who dont like to talk much are not necessarily shy; they _ just be quiet people.Amust BmayCshould Dwould答案與解析：B句意：一些不喜歡多說(shuō)話的人不一定就害羞，他們可能只是安靜的人。4(2009遼寧)The traffic is heavy these da

28、ys, I _ arrive a bit late, so could you save me a place?Acan BmustCneed Dmight答案與解析：D句意：這些天交通很擁擠。我可能遲到，因此請(qǐng)給我留個(gè)位子好嗎？四個(gè)選項(xiàng)中，只有might表示“可能”，用于肯定句。5(2009全國(guó))I cant leave. She told me that I _ stay here until she comes back.Acan BmustCwill Dmay答案與解析：B句意：我不能離開(kāi)。她對(duì)我說(shuō)過(guò)，我得在這里待到她回來(lái)。選項(xiàng)A表示能力或許可；選項(xiàng)B表示必須；選項(xiàng)C表示將要；選項(xiàng)D表

29、示可以。根據(jù)語(yǔ)境可知，選項(xiàng)B合適。6(2009江蘇)He did not regret saying what he did but felt that he _ it differently.Acould expressBwould expressCcould have expressedDmust have expressed答案與解析：C根據(jù)語(yǔ)境知道，后半句表示對(duì)過(guò)去某種情況的揣測(cè)，所以首先排除A和B兩項(xiàng)。另外，C項(xiàng)表示“本能夠做某事，而沒(méi)有做”；D項(xiàng)表示“過(guò)去一定做過(guò)某事”。根據(jù)語(yǔ)境，知C項(xiàng)合適。7(2009浙江)The doctor recommended that you _ sw

30、im after eating a large meal.Awouldnt BcouldntCneednt Dshouldnt答案與解析：D句意：醫(yī)生建議說(shuō)在吃過(guò)飽飯后不要游泳。recommend作“建議”解，后面的賓語(yǔ)從句用虛擬語(yǔ)氣，謂語(yǔ)動(dòng)詞為“should (not)動(dòng)詞原形“。8(2008浙江)You _ be hungry alreadyyou had lunch only two hours ago!Awouldnt BcantCmustnt Dneednt答案與解析：B句意：你不可能(現(xiàn)在就已)餓了你兩個(gè)小時(shí)前剛吃的午飯。cantdo表示對(duì)現(xiàn)在情況的推測(cè)，can表推測(cè)，常用于否定句

31、和疑問(wèn)句中；must表推測(cè)只用于肯定句中，mustnt意為“禁止，一定不能”。wouldntdo常表示對(duì)現(xiàn)在或?qū)?lái)情況的虛擬，neednt do意為“沒(méi)必要做”。9(2008福建)It is usually warm in my hometown in March, but it _ be rather cold sometimes.Amust BcanCshould Dwould答案與解析：B這里的意思是有時(shí)天氣可能會(huì)相當(dāng)冷。can用在此處表示可能性。must必須，肯定；should應(yīng)該；would過(guò)去常常。10(2008天津)She _ have left school, for her

32、bike is still here.Acant BwouldntCshouldnt Dneednt答案與解析：A此題考查情態(tài)動(dòng)詞表示推測(cè)意義的用法。句意：她不可能已離開(kāi)學(xué)校，因?yàn)樗淖孕熊囘€在這兒。根據(jù)句意可知選擇cant, can/could have done表示對(duì)過(guò)去的推測(cè)，常用于否定句、疑問(wèn)句中。wouldnt have done常表示虛擬。shouldnt have done本來(lái)不應(yīng)該做而做了；neednt have done本來(lái)沒(méi)必要做而做了。.模擬題1(2009東北三校聯(lián)考)Why _ it rain on Sunday? We cant go camping as plann

33、ed. What a pity!Ashould Bcan Cmust Dmay答案與解析：C由句意：為什么星期日偏偏下雨？害得我們不能按計(jì)劃去野營(yíng)了，真遺憾！知在抱怨，而must則可表示“非得；偏偏”，故C項(xiàng)合句意。2(2009南寧適應(yīng)性測(cè)試) The woman biologist stayed in Africa studying wildlife for 13 years before she returned to her country. Oh, dear! She _ a lot of difficulties.Amay go throughBmight go throughCmu

34、st have gone throughDought to have gone through答案與解析：CC項(xiàng)表示“肯定是經(jīng)歷了”。根據(jù)句意：在回國(guó)前在非洲呆了13年，表示“對(duì)過(guò)去所發(fā)生事的肯定推測(cè)”；D項(xiàng)表示“本該做某事而未做，同should have done”。A、B兩項(xiàng)不能表達(dá)與過(guò)去的關(guān)系。3(2009揚(yáng)州調(diào)研)Could I get the passport in 20 days?It depends.Anyway，you _ have my answer tomorrow.Acould BmustCshall Dneed答案與解析：C根據(jù)It depends.可知不確定。句意：無(wú)

35、論能否，你明天就會(huì)聽(tīng)到我的答復(fù)。表示對(duì)對(duì)方的承諾。而shall有此用法。could能夠；must必須；need需要。4(2009贛州摸底考試)You_have carried all these parcels yourself. The shop would have delivered them if you had asked them.Aneednt Bmustnt Cshouldnt Dcouldnt答案與解析：Aneednt沒(méi)必要做而做了，據(jù)“The shop would have delivered.”，知選A項(xiàng)。B項(xiàng)中，mustnt不能用于此結(jié)構(gòu)；shouldnt本不該做而做了

36、；couldnt本不可能卻做到了。5(2009成都診斷性檢測(cè))The old people each _ get a very nice present from our manager on their birthdays.Great! It must be a big surprise to them.Amust BshallCwould Dshould答案與解析：B情態(tài)動(dòng)詞shall用于第二、三人稱時(shí)可以表示允諾、命令、威脅、警告、決心等，本題中的shall表示“允諾，許諾”。其他選項(xiàng)用在這里不合適。6(2009貴州適應(yīng)性考試)Where is Lily, Lucy? I cannot

37、find her anywhere.She _ have been off long. I saw her clean the window just now.Ashouldnt BcantCmustnt Dneednt答案與解析：B據(jù)句意應(yīng)為“不可能”，所以選B項(xiàng)。shouldnt不該做而做了；neednt沒(méi)必要做而做了。C項(xiàng)無(wú)此用法。7(2009淄博質(zhì)檢)The public transport in Beijing is very convenient now, so there _ be any difficulty in travelling around the city.Acou

38、ldnt BmustntCneednt Dshouldnt答案與解析：D由句意：北京的公共交通很方便。推知下句“因此環(huán)城旅行不會(huì)困難”。shouldnt(按常理推測(cè))不該。couldnt不可能；mustnt不可以；neednt沒(méi)必要。8(2009濰坊質(zhì)檢)My mother is a great cook and we _ never get enough of her cookies.Amay BneedCshould Dcan答案與解析：D由句意：好廚師，她做的甜餅我們永遠(yuǎn)吃不夠。知選can能夠，表示推測(cè)。may也可表示推測(cè)，但語(yǔ)氣較弱。9(2009西安八校聯(lián)考)In crowded pl

39、aces like railway stations and airports, you _ take care of your luggage.Amust BmayCwill Dcan答案與解析：A句意：在諸如火車站和機(jī)場(chǎng)等人群擁擠之處，你必須照看好你的行李。must 必須。又如：If you cant finish the book by then, you must come and renew it. 如果到時(shí)候你看不完這本書，就必須來(lái)續(xù)借。10(2009大連模擬)Did you attend your sons graduation ceremony yesterday? I_， but I had to go t