高中英語語法總結(jié)大全之情態(tài)動詞

1、精選優(yōu)質(zhì)文檔-傾情為你奉上高中英語語法總結(jié)大全之情態(tài)動詞情態(tài)動詞的語法特征 1） 情態(tài)動詞不能表示正在發(fā)生或已經(jīng)發(fā)生的事情，只表示期待或估計某事的發(fā)生。2） 情態(tài)動詞 除ought 和have 外，后面只能接不帶to 的不定式。3） 情態(tài)動詞沒有人稱，數(shù)的變化，即情態(tài)動詞第三人稱單數(shù)不加-s。4） 情態(tài)動詞沒有非謂語形式，即沒有不定式，分詞，等形式。 w.w.w.k.s.5.u.c.o.m 比較can 和be able to 1）can，could 表示能力；可能 (過去時用could), 只用于現(xiàn)在式和過去式(could)。be able to可以用于各種時態(tài)。They will be ab

2、le to tell you the news soon. 他很快就能告訴你消息了。2）只用be able to a. 位于助動詞后。b. 情態(tài)動詞后。c. 表示過去某時刻動作時。 d. 用于句首表示條件。e. 表示成功地做了某事時，只能用was/were able to， 不能用could。He was able to flee Europe before the war broke out.= He managed to flee Europe before the war broke out.注意：could不表示時態(tài)1）提出委婉的請求，（注意在回答中不可用could）。 - Could

3、 I have the television on? - Yes, you can. / No, you can't.2）在否定，疑問句中表示推測或懷疑。 He couldn't be a bad man. 他不大可能是壞人。 w.w.w.k.s.5.u.c.o.m 比較may和might 1） 表示允許或請求；表示沒有把握的推測；may 放在句首，表示祝愿。May God bless you!He might be at home.注意： might 表示推測時，不表示時態(tài)。只是可能性比may 小。2） 成語： may/might as well，后面接不帶to 的不定式，意

4、為"不妨"。If that is the case, we may as well try.典型例題Peter _come with us tonight, but he isn't very sure yet. A. must B. may C. can D. will答案B. 表可能性只能用may.此句意可從后半句推出。 w.w.w.k.s.5.u.c.o.m 比較have to和must 1)兩詞都是'必須'的意思，have to 表示客觀的需要， must 表示說話人主觀上的看法，既主觀上的必要。My brother was very ill

5、, so I had to call the doctor in the middle of the night.我弟弟病得很厲害，我只得半夜里把醫(yī)生請來。(客觀上需要做這件事)He said that they must work hard. 他說他們必須努力工作。（主觀上要做這件事） 2)have to有人稱、數(shù)、時態(tài)的變化，而must只有一種形式。但must 可用于間接引語中表示過去的必要或義務(wù)。He had to look after his sister yesterday.3） 在否定結(jié)構(gòu)中： don't have to表示"不必"mustn't

6、表示"禁止"， You don't have to tell him about it.你不一定要把此事告訴他。 You mustn't tell him about it.你一定不要把這件事告訴他。 w.w.w.k.s.5.u.c.o.m must表示推測 1) must用在肯定句中表示較有把握的推測，意為"一定"。2) must表對現(xiàn)在的狀態(tài)或現(xiàn)在正發(fā)生的事情的推測時， must 后面通常接系動詞be 的原形或行為動詞的進行式。 You have worked hard all day. You must be tired.你辛苦干一

7、整天，一定累了。（對現(xiàn)在情況的推測判斷）He must be working in his office. 他一定在辦公室工作呢。比較： He must be staying there. 他現(xiàn)在肯定呆在那里。He must stay there. 他必須呆在那。 3) must 表示對已發(fā)生的事情的推測時，must 要接完成式。 I didn't hear the phone. I must have been asleep.我剛才沒有聽到電話，我想必是睡著了。4) must表示對過去某時正發(fā)生的事情的推測，must 后面要接不定式的完成進行式。-Why didn't you

8、 answer my phone call?-Well, I must have been sleeping, so I didn't hear it.5) 否定推測用can't。 If Tom didn't leave here until five o'clock, he can't be home yet.如果湯姆五點才離開這兒，他此時一定還未到家。 w.w.w.k.s.5.u.c.o.m 表示推測的用法 can, could, may, might, must 皆可表示推測，其用法如下：1）情態(tài)動詞+動詞原形。表示對現(xiàn)在或?qū)淼那闆r的推測，此時動

9、詞通常為系動詞。I don't know where she is, she may be in Wuhan.2）情態(tài)動詞+動詞現(xiàn)在進行時。表示對現(xiàn)在或?qū)碚谶M行的情況進行推測。At this moment, our teacher must be correcting our exam papers.這時，我們老師想必在批改試卷。3）情態(tài)動詞+動詞完成時。表示對過去情況的推測。We would have finished this work by the end of next December.明年十二月底前我們很可能已完成這項工作了。The road is wet. It mu

10、st have rained last night.地是濕的，昨天晚上一定下雨了。4）情態(tài)動詞+動詞的現(xiàn)在完成進行時。表示對過去正在發(fā)生事情的推測。Your mother must have been looking for you.你媽媽一定一直在找你。5）推測的否定形式，疑問形式用can't, couldn't表示。Mike can't have found his car, for he came to work by bus this morning.邁克一定還沒有找回他的車，因為早上他是坐公共汽車來上班的。注意：could, might表示推測時不表示時態(tài)，其

11、推測的程度不如can, may。 w.w.w.k.s.5.u.c.o.m 情態(tài)動詞+have+過去分詞 1) may(might) have + done sth, can (could) have + done sth表示過去，推測過去時間里可能發(fā)生的事情。Philip may (might) have been hurt seriously in the car accident.Philip can (could) have been hurt seriously in the car accident.2)must have +done sth，對過去時間里可能發(fā)生的事情的推測，語氣較

12、強，具有"肯定"，"諒必"的意思。-Linda has gone to work, but her bicycle is still here.-She must have gone by bus.3) ought to have done sth, should have done sth本應(yīng)該做某事，而事實上并沒有做。否定句表示"不該做某事而做了"。You ought to (should) have been more careful in this experiment.He ought not to have thrown

13、the old clothes away.（事實上已扔了。）ought to 在語氣上比should 要強。4) needn't have done sth本沒必要做某事I dressed very warmly for the trip, but I needn't have done so. The weather was hot.5) would like to have done sth本打算做某事I would like to have read the article, but I was very busy then. w.w.w.k.s.5.u.c.o.m sh

14、ould和ought to should 和ought to 都為"應(yīng)該"的意思，可用于各種人稱。-Ought he to go?-Yes. I think he ought to.表示要求，命令時，語氣由 should（應(yīng)該）、had better最好）、must（必須）漸強。 w.w.w.k.s.5.u.c.o.m had better表示最好 had better 相當于一個助動詞，它只有一種形式，它后面要跟動詞原形。had better do sth had better not do sthIt is pretty cold. You'd better p

15、ut on my coat.She'd better not play with the dog. had better have done sth表示與事實相反的結(jié)果，意為"本來最好"。You had better have come earlier. w.w.w.k.s.5.u.c.o.m would rather表示"寧愿" would rather dowould rather not dowould rather than寧愿而不愿。還有would sooner, had rather, had sooner都表示"寧愿&qu

16、ot;、"寧可"的意思。If I have a choice, I had sooner not continue my studies at this school.I would rather stay here than go home. = I would stay here rather than go home.典型例題-Shall we go skating or stay at home?-Which _ do?A. do you rather B. would you ratherC. will you rather D. should you rathe

17、r答案B。本題考查情態(tài)動詞rather的用法，would rather +do sth 意為"寧愿"，本題為疑問句，would 提前，所以選B。 w.w.w.k.s.5.u.c.o.m will和would would rather dowould rather not dowould rather than寧愿而不愿。還有would sooner, had rather, had sooner都表示"寧愿"、"寧可"的意思。If I have a choice, I had sooner not continue my studie

18、s at this school.I would rather stay here than go home. = I would stay here rather than go home.典型例題-Shall we go skating or stay at home?-Which _ do?A. do you rather B. would you ratherC. will you rather D. should you rather答案B。本題考查情態(tài)動詞rather的用法，would rather +do sth 意為"寧愿"，本題為疑問句，would 提前，

19、所以選B。 w.w.w.k.s.5.u.c.o.m 情態(tài)動詞的回答方式 問句 肯定回答 否定回答Need you?Yes, I must. No, I needn'tMust you?/don't have to. 典型例題1）-Could I borrow your dictionary?-Yes, of course, you_.A. might B. will C. can D. should答案C. could表示委婉的語氣，并不為時態(tài)。答語中of course，表示肯定的語氣，允許某人做某事時，用can和 may來表達，不能用could或might。復習： will

20、與you連用，用來提出要求或下命令。should與you 連用，用來提出勸告。2）-Shall I tell John about it?-No, you _. I've told him already.A. needn't B. wouldn't C. mustn't D. shouldn't答案A。needn't 不必，不用。 wouldn't 將不, 不會的。 mustn't 禁止、不能。 shouldn't不應(yīng)該。本題為不需要，不必的意思，應(yīng)用needn't。3）-Don't forget to

21、come to my birthday party tomorrow.-_.A. I don't B.I won't C. I can't D. I haven't 答案B. will既可當作情態(tài)動詞，表請求、建議、也可作為實義動詞表"意愿、意志、決心"，本題表示決心，選B。 w.w.w.k.s.5.u.c.o.m 帶to的情態(tài)動詞 帶to 的情態(tài)動詞有四個：ought to, have to, used to, be to, 如加上have got to ,(=must), be able to，為六個。它們的疑問，否定形式應(yīng)予以注意：Do they have to pay their bill before the end of the month?She didn't use to play tennis before sh