情態(tài)動(dòng)詞的用法歸納

1、情態(tài)動(dòng)詞的用法要點(diǎn)can和 could情態(tài)動(dòng)詞用法例句can/could表示能力1“I don't think Mike can type. ” “Yes,he can”.2Ican speak fluent English now,but I couldn't last year.在肯定句中，表示客觀可能 性，并不涉及具體某事會(huì)發(fā) 生，常用來說明人或事物的 特征。要表達(dá)具體某事實(shí)際 發(fā)生的可能性時(shí)，不用 can， 需用 could， may， might 。1As a human being, anyone can make a mistake. 2I'm confi

2、dent that a solution can be found.3He can be very forgetful sometimes.4I may stay at home this weekend（. 實(shí)際可能性）5Peter might come to join us.（實(shí)際可能性 ）6It will be sunny in the daytime ,but it could rain tonight. （實(shí)際 可能性 ）表示請(qǐng)求和允許。表示請(qǐng)求， 口語中常用 could 代替 can， 使語氣更委婉。1Can we turn the air conditioner on?2Any

3、police officer can insist on seeing a driver's license. 3In soccer,you can't touch the ball with your hands.4Could you have her call me back when she gets home,please 5I wonder if I could just ask you to sign this.表示對(duì)現(xiàn)在的動(dòng)作或狀態(tài)進(jìn) 行主觀的猜測(cè)，主要用在否 定句和疑問句中。1It can't be easy caring for a man and a

4、 child who are not your own.2Can the man over there be our head master?表示驚異、懷疑、不相信等 態(tài)度，主要用在否定句、疑 問句和感嘆句中。1Can this be an excuse for not giving them help?2This can't be true.3How can you be so crazy.特別說明：（1）could 用來表示請(qǐng)求時(shí)，語氣委婉，主要用于疑問句，不能用于肯定句，答語應(yīng)用can（即： could 不能用于現(xiàn)在時(shí)態(tài)的簡(jiǎn)略答語中） 。如： Could I use your d

5、ictionary? Yes, you can.（否定回答可用： No, I 'm afraid not.）（2）can和 be able to辨析can（could）和 be able to都可以表示能力，意思上沒有區(qū)別。但can只有現(xiàn)在式和過去式，而 be able to 則有更多的形式。如：I've always wanted to able to speak fluent English.Those bags look really heavy,are you sure you 'll be able to carry them on your own? 但是，

6、表示在過去某時(shí)的某一場(chǎng)合經(jīng)過一番努力，終于做成了某事，通常不用could，而用 was/were able to 來表示。這時(shí)， was/were able to 相當(dāng)于 managed to do或 succeed in doing。如：After the accident it was a long time before she was able to walk again.The fire was very big, but most people were able to escape from the building.（3）慣用形式“ cannot too ”表示“無論怎么也不（

7、過分） ”。如： You cannot be too careful. 你越小心越好。慣用形式“ cannot but+ 不定式（不帶 to）”表示“不得不，只好” 。如： I cannot but admire her determination. 我不得不欽佩你的決心。may 和 might情態(tài)動(dòng)詞用法例句表示允許、許可。否定回答一般用 must not/mustn 't,1May I come in and wait?表示“禁止、阻止”之意，但也可以用 had better not2 May I smoke here?（最好別 ）或 may not（不可以） ，語氣較為委婉。 N

8、o, you mustn 't( 或 No, you 'd better not.)在表示請(qǐng)求、允許時(shí)， might 比 may 語氣更委婉1Might I borrow your pen?些。用 May I 征詢對(duì)方許可在文體上比較正式， 在口氣上比較客氣， 在日常用語中， 用 Can I 征詢 對(duì)方意見更為常見。2I wonder if I might speak to your son.表示可能性的推測(cè)， 通常用在肯定句和否定句中，1It may rain this afternoon.含有“或許” “大概”“可能”之意；用 might 代2She might come

9、to join us this afternoon.may/might替 may 時(shí)，則語氣顯得更加不肯定。3I suppose he might have missed the train.1May you succeed.may 用于祈使句表示祝愿2Long may he live! 愿他能持續(xù)住下去。3May you have many more days as happy as this one.4May she rest in peace.愿她安息。慣用句式：1It may well change forever the way you look at Greek“ may well

10、+ 動(dòng)詞原形”，意為“完全能， 很可能”，art.相當(dāng)于 to be very likely to2There may well be a real problem here.3There is nothing to do, so I may as well go to bed.“ may as well 或 might(just)as well+ 動(dòng)詞原形”意4You may as well tell us now, we 'll find out sooner or為“最好，滿可以，倒不如” ，相當(dāng)于“ had betterlater.或 there is no reason to

11、 do anything else.5I suppose we might as well go home.6And if you have to plough the field anyway, you might as well plant it at the same time.must 和 have to情態(tài)動(dòng)詞用法例句must表示“必須，應(yīng)該”之意，語氣比 should ， ought to 強(qiáng)烈。其否定形式 mustn't 表示“不準(zhǔn)，不應(yīng)該，禁 止”等意1 You must come to school on time.2 Everybody must obey the

12、law.3 You mustn 't drive so fast in the street.4 We mustn't waste any more time.在回答帶有 must 的問句時(shí)，否定回答常用 needn't 或 don 't have to，表示“不必” ，而不用 mustn't1 Must I come back before ten? Yes， you must.(No, you needn 't)表示有把握的推測(cè)，意為“一定、準(zhǔn)是、相必” ，只1 It must be my mother.用于肯定句中2 You must be

13、 hungry after a walk.3 There must be a hole in the wall.have tohave to“必須，不得不” ，意義與 must 相近。但 must 表示 的是說話人的主觀看法， 而 have to則往往強(qiáng)調(diào)客觀 需要。1 The film is not interesting. I really must go now.2 I have to go now, because my mother is in hospital.must 只有一種形式，即現(xiàn)在式與過去式都是一種形 式，而 have to則涉及各種人稱、 時(shí)態(tài)等方面的變化 形式。1 I

14、 had to work hard when I was your age.2 I will have to learn how to use a computer.3 In order to take the exam, we 'll have to finish the whole book by the end of this month .兩者的否定意義不同， mustn't 表示“禁止，不許” ， don 't have to 表示不必。1 You mustn 't go there. 2 You don't have to go there.

15、四 shall和 should情態(tài)動(dòng)詞用法例句shall用于第一、二、三人稱構(gòu)成的疑問句，表示征求1Shall I open the window?對(duì)方意見或請(qǐng)求指示2Shall we say 6 o'clock, then?3What shall I get for dinner?用于第二、三人稱陳述句中，表示說話人給對(duì)方1Don 't worry, you shall get the answer this的命令、警告、允諾或威脅。afternoon.（ 允諾 ）2He shall be sorry for it one day, I tell you. （警告）3You

16、shall do as I say. （命令 ）4If you children don 't do as I tell you, you shall notgo to the party. （威脅 ）should表示勸告或建議，意為“應(yīng)該”1What should I do?2Should I trust him?3You should read his new book.表示推測(cè)，用在肯定句中，對(duì)現(xiàn)在的情況或可能1It should be a nice day tomorrow.發(fā)生2Try phoning Robert, he should be home now.的事的主觀推測(cè)

17、或期待。意為“想必，大概，或3He should be around sixty years old.許”還可以用在 if 引導(dǎo)的條件句中，表示一件事聽起1Ask Tom to ring me up if you should see him. （ 你來可能性很小， 但也不是完全不可能，相當(dāng)于“萬萬一見到湯姆，請(qǐng)讓他給我打個(gè)電話 )一”的意思。從句謂語用 should+ 動(dòng)詞原形構(gòu)成，2Should I be free tomorrow, I 'll come. （ 萬一我明天主句都一定用虛擬語氣有時(shí)間，我就過來 )3If things should change suddenly,

18、please let meknow. ( 萬一情況突變，請(qǐng)通知我 )用于疑問句或感嘆句中， 表示意外、驚異的情緒，1Why should anyone want to marry Tony?意為“竟會(huì)” ，與 why ， what， how， who 連用，2Don 't ask me. How should I know?如果是疑問句，則不需要回答。五 will 和 would情態(tài)動(dòng)詞用法例句will/would用于表示意志或意愿。 will 指現(xiàn)在， would1He is the man who will go his own way. ( 他首歌自行其指過去。是的人。 )2Th

19、ey said they would meet us at 10:30 at the station.表示請(qǐng)求、 建議等，用 would 比用 will 委婉、1Will you please take a message for him?客氣。2Would you please tell me your telephone number?表示習(xí)慣或傾向，意為“總是，慣于” 。will1Fish will die without water.至現(xiàn)在， would 指過去。2People will talk. ( 人們總會(huì)說閑話。 )3When we worked in the same off

20、ice, we would often havecoffee together.表示推測(cè)，意為“很可能，大概” 。 will 表1These things will happen.示推測(cè)比 should 把握大，比 must 把握小。2That will be the messenger ringing.3It would be about ten o 'clock when he left home.表示功能，意為“能，行” 。慣用形式： will1That will be all right.do/would do 表示“解決問題” 、“就行”。2Either pen will d

21、o.3It would not do to work too late. (工作太晚不行。 )用于否定句中，意為“不肯” 、“不樂意”1I won 't listen to your nonsense.2No matter what I said, he wouldn 't listen to me.特別說明： would 與 used to辨析would 可用來表示過去反復(fù)出現(xiàn)的動(dòng)作， 但不能表示過去存在的狀態(tài)， 所以我們不能說： “ she would be a quiet girl. 另外， would 強(qiáng)調(diào)過去某種特定情況下的活動(dòng)，是完全過去的事情，同現(xiàn)在沒有聯(lián)系。而

22、used to 則著眼于過去和現(xiàn)在 的對(duì)比，隱含現(xiàn)在已不存在，動(dòng)作或狀態(tài)都可表示。 Would 可以表示不規(guī)則的習(xí)慣， used to 則不可。如：He used to be a naughty boy and cause trouble.I used to get up at six in the morning.Sometimes she would take a walk in the neighboring woods.In those days, whenever I had difficulties, I would go to Mr. Chen for help.六 need和

23、dare情態(tài)動(dòng)詞用法例句用于表示“需要，必要”之意。做情態(tài)動(dòng)詞時(shí)， 僅用于否定句和疑問句，只有現(xiàn)在時(shí)，過去式 要用 needn't have，疑問式用 need+人稱 ?,否定式 用 need not( 即 needn't)，1 Need we leave soon? Yes, you must.(No, you needn't) 2 You needn't have hurried.(=It was not necessary for you to hurry ， but you did). 你 當(dāng)時(shí)不必這么匆忙。need做實(shí)義動(dòng)詞時(shí)，其變化與一般的實(shí)義動(dòng)詞相

24、同， 后接帶 to 的不定式( need doing = need to be done ) ,過去式用 needed 、did you need? 和 didn't need, 肯定式用 needs/needed/need, 疑問 式用 do、 does 、 did 提問，否定式要在前面加 don't 、 doesn't 、 didn't1. A job like nursing needs patience and understanding.(need+名詞， need understanding=need to be understood,需要被理解 )

25、2 He needs to see a doctor.(need to do)3 Do you still need volunteers to help clean up after the party?(need somebody to do something)4 They didn't need to start so early.（do not need to do）dare用于表示“敢于”之意。做情態(tài)動(dòng)詞，沒有人 稱和數(shù)的變化，主要用于否定句、疑問句和條 件狀語從句中1 Dare you tell her the truth? Yes, I dare. /No, I dar

26、en 't.3 How dare you accuse me of lying! 4 He daren't admit this.用作實(shí)義動(dòng)詞時(shí)，其變化與一般的實(shí)義動(dòng)詞相 同。在肯定句中， dare 后接帶 to 的不定式；否 定句中， dare 后既可接帶 to 的不定式，也可接 不帶 to 的不定式。1 Only a few journalists dared to cover the story.2 He doesn't dare （to） go there alone.3 Don 't you dare （to） touch it?七 ought的用法：

27、情態(tài)動(dòng)詞用法例句ought to do表示“應(yīng)該”之意1 You ought to take care of him.2 Ought I go now? Yes, you ought to. /No, you oughtn 't to.表示推測(cè)。注意與 must 表示推測(cè)是的區(qū)別1 He must be home by now. （ 斷定他已到家 ） 2 He ought to be home by now. （ 不十分肯定 ） 3 This is where the oil must be. （ 比較直率 ） 4 This is where the oil ought to be.

28、（ 比較含蓄 ）說明： should與ought to 表示“應(yīng)該”時(shí)的區(qū)別 should 表示自己的主觀看法，而 ought to 的語氣中，含有“按道理應(yīng)該”之意。若要反映客觀情況或涉及法 律義務(wù)和規(guī)定，一般用 ought to。如：You should help them with their work.You are his father. You ought to get him to receive good education.八“情態(tài)動(dòng)詞 +have done”用法情態(tài)動(dòng)詞 +have done用法例句must have done表示主觀上對(duì)過去已經(jīng)發(fā)生的行為進(jìn)行 推測(cè)， 意為

29、“想必， 準(zhǔn)是， 一定做了某事”1 She must have gone through a lot.2 He must have visited the White House during his stay in the United States.may/might have done表示對(duì)過去已發(fā)生行為的推測(cè)，意為“也 許/或許已經(jīng)（沒有） “。一般用于肯 定句或否定句中， 不用于疑問句。 用 might 則表示語氣更加不肯定。1 You may have learnt the news.2 He may not have heard his name called.3 Sorry I

30、 'm late. I might have turned off the alarm clock and gone back to sleep again.can have done cannot have done表示對(duì)過去發(fā)生的行為的懷疑和不肯定， 通常用在否定句和疑問句中。 （ can 換成 could 時(shí)語氣委婉）1 Where can she have gone?2 Could he have done such a foolish thing?3 The boy can't have finished reading the book so soon because it is difficult even to an adult.could have done可用于肯定句中，表示“可能已經(jīng)” 之意，此外，還可以表示過去能做而沒做 的事，有一種對(duì)過去為付諸實(shí)施的事情的 惋惜。1 He could have killed himself driving at a dangerous speed.2 You could have been more considerate.3 You could have done better, but you were too careless.migh