情態(tài)動(dòng)詞(07年版).ppt

1、情態(tài)動(dòng)詞,一、常見(jiàn)的功能： 1. 請(qǐng)求對(duì)方許可： Can/May/Could/Might I? （can多用于口語(yǔ)中，常用于第一人稱(chēng)表示請(qǐng)求允許做某事；could 較客氣，may/might用于正式場(chǎng)合，語(yǔ)氣較恭敬，might更客氣。） 應(yīng)答時(shí)用can或may,不用could或might. e.g. -Could I borrow your bike? -Yes, of course you can.,2. 表示可能性： (1) 詢(xún)問(wèn)是否有可能性 疑問(wèn)句中常用can/could/might, 一般不用may e.g. Can/Could/Might it be a true story? 這會(huì)

2、是真實(shí)情況嗎？ (2) 可能性的否定 may/might not表示某動(dòng)作或狀態(tài)可能不會(huì)發(fā)生或存在 cant/couldnt 表示某動(dòng)作或狀態(tài)不可能會(huì)發(fā)生或存在 e.g. He may/might not have enough money for a new car. 他可能沒(méi)有足夠的錢(qián)買(mǎi)新車(chē)。 He cant /couldnt have enough money for a new car. 他不可能有足夠的錢(qián)買(mǎi)新車(chē)。,3. 詢(xún)問(wèn)是否必須做某事 常用句型：Must I ? / Need I ? （注意應(yīng)答） e.g. -Must I wait until they come? -Yes,

3、you must. -No, you neednt. / No, you dont have to. / No, you dont neednt to. -Need we go over all the old lessons? -Yes, you must. 4.表示沒(méi)有必要做某事 常用neednt, dont have to, dont need to表示 e.g. You neednt / dont have to / dont need to do that.,二、注意點(diǎn)： 1. can / could 的用法 (1) 表示能力 C.f: can/could與be able to 的區(qū)

4、別： A: can/could表示現(xiàn)在和過(guò)去的能力，而be able to用于更多的時(shí)態(tài) B: 表示經(jīng)過(guò)努力而成功地做成了某件具體的事情時(shí)，只能用was/were able to=managed to do =succeeded in doing e.g. The fire spread through the hotel very quickly, but everyone was able to get out.,(2) 表示許可：在疑問(wèn)句中could比can語(yǔ)氣更委婉。 e.g. Could you come a little earlier? (3) 表示可能性：用在疑問(wèn)句和否定句中。

5、 e.g. Can she live here? It cant be true. (4) can可指一時(shí)的情況，譯為“有時(shí)候會(huì)” e.g. He can be very friendly at times. Our house is on the top of the hill, and in winter the winds can be pretty cold. He is a bad-tempered fellow, but he can be quite charming when he wishes.,2. may/ might的用法 (1) 表示允許，may語(yǔ)氣正式，側(cè)重說(shuō)話(huà)人的

6、許可。 e.g. You may take the book home. (2) 表示可能性，不用于疑問(wèn)句。might 比may可能性小。 e.g. They may not be there today. (3) 表示祝愿、祝福。 e.g. May you succeed! May you be happy!,3. shall的用法： (1) shall用于第一、三人稱(chēng)疑問(wèn)句中，表示說(shuō)話(huà)人征求對(duì)方的意見(jiàn)或向?qū)Ψ秸?qǐng)求 e.g. Shall we begin our class? When shall he be able to leave the hospital? (2) shall用于第二

7、、三人稱(chēng)的陳述句中，表示說(shuō)話(huà)人的某種感情，如命令，警告，允諾，決心，威脅等。 e.g. You shall have a new bicycle on your birthday.(允諾) He shall have the book when I finish reading.(允諾),You shall fail if you dont work harder. (警告) If you will not obey me, you shall leave the house. 如果你不服從我，你必須離開(kāi)這里。 If you children wont do as I tell you, yo

8、u shant go to the park.,4. should 的用法 (1) should用于含有surprising, amazing, shocked, sorry, ashamed等詞的句子中，譯為“居然，竟然”。 e.g. Im terribly sorry that they should think I did it on purpose. 我十分遺憾，他們居然認(rèn)為我是故意做的。 若強(qiáng)調(diào)事情已發(fā)生，可用should have done e.g. I was shocked that she should have done such a thing like that. 她居

9、然做了那種事，我十分吃驚。,(2) should可表示說(shuō)話(huà)者根據(jù)常理或常態(tài)對(duì)現(xiàn)在、將來(lái)或過(guò)去情況進(jìn)行某種推測(cè)，可譯為“可能，該” e.g. -When can I come for the photos? I need them tomorrow afternoon. -They _ be ready by 12:00. A. can B. should C. might D. need e.g. He should be taking a bath now. She has been studying hard. She should do well on the test tomorrow

10、. 她一直努力學(xué)習(xí)，明天的測(cè)驗(yàn)她應(yīng)該考得好。 He should arrive at noon. 他該在中午到達(dá)。 They should have arrived at 8:30, but they didnt turn up. 他們本該在八點(diǎn)半到達(dá)，但他們并沒(méi)有露面。,5. will 的用法 (1) 表示意志、愿望和決心(用于各種人稱(chēng)) e.g. I will never do that again. If you will listen, I will give you some advice. (if條件句中的will表示“愿意”而不是將 來(lái)時(shí)態(tài)) 不愿意用wont. e.g. If

11、they wont accept a cheque, well have to pay cash. (2) 談?wù)摿?xí)慣和特性（would 表示過(guò)去的習(xí)慣行為或 特有的行為），含有“總是”，“習(xí)慣于”的意思。 e.g. He will arrive last and will be the first to leave. 他總是到得最后，走得最早。 Boys will be boys. Mr. Brown would go fishing on Sundays when he worked in that town.,(3) 表示一種傾向，一種不能控制的事，一種必然(普遍真理，自然傾向及事物品質(zhì))

12、 e.g. Man will die without water. 人沒(méi)有水會(huì)死的。 (4) 物做主語(yǔ)時(shí)，will表示固有性質(zhì)、功能，表示“因出毛病而不能”, 相當(dāng)于There is something wrong with sth. 的含義。 e.g. The bus wont start. 汽車(chē)開(kāi)不動(dòng)了。 The door wont open. Oil and water wont mix.,6. must的用法 （1）表示主觀必須，而have to表示客觀不得不。 （2）表示推測(cè)，只用于肯定句，若要表示“不可能”， “一定不”用cant。 （3）表示“偏偏，硬要（做令人不快的事）” e.

13、g. The telephone must ring when I was busy in the kitchen. After I gave her my advice, she must go and do the opposite. Just when we were ready to go away for the holidays, the baby must catch a bad cold.,The car must break down just when we were about to start off. 我們正要出發(fā)時(shí)偏偏車(chē)壞了。 At a time when ever

14、ybody was in bed, he must turn his radio on. 大家都上床休息時(shí)他偏偏打開(kāi)了收音機(jī)。,7. need & dare (1) 作情態(tài)動(dòng)詞時(shí)，要直接跟動(dòng)詞，直接提問(wèn)，直接否 定；作行為動(dòng)詞時(shí)則沒(méi)有這些特征 (2) 在否定句和疑問(wèn)句中，need既可作情態(tài)動(dòng)詞又可 作行為動(dòng)詞；在否定句、疑問(wèn)句和條件句中， dare 既可作情態(tài)動(dòng)詞又可作行為動(dòng)詞（常用作情 態(tài)動(dòng)詞）。 在肯定句中need和dare通常作行為動(dòng)詞。 (3) 作情態(tài)動(dòng)詞時(shí)，need沒(méi)有過(guò)去式，而dare有過(guò)去 式，為dared. (4) 作行為動(dòng)詞時(shí)，在肯定句中，need 和dare后面 的動(dòng)詞是

15、帶to 的不定式。在否定句和疑問(wèn)句中， dare 后面的不定式可帶to, 也可以省略to. e.g. He needs to work harder. They dare to swim across the river. He doesnt dare (to) answer.,7. 表示推測(cè)的情態(tài)動(dòng)詞 (1) 用于肯定推測(cè)的有：must(語(yǔ)氣最強(qiáng)), may, might(語(yǔ)氣最弱) 用于否定推測(cè)和疑問(wèn)推測(cè)的有：cant, couldnt (2) 對(duì)現(xiàn)在情況的推測(cè)：情態(tài)動(dòng)詞+do 對(duì)正在進(jìn)行的動(dòng)作的推測(cè)：情態(tài)動(dòng)詞+be doing e.g. You must be waiting for s

16、omeone. 你 一定在等人吧。 (3) 對(duì)過(guò)去動(dòng)作的推測(cè)：情態(tài)動(dòng)詞+have done,9. 情態(tài)動(dòng)詞+have done (1) must + have done 對(duì)過(guò)去情況的肯定推測(cè)，“肯定發(fā)生了某事”。 e.g. It must have rained last night. (2) should / ought to +have done 本該做而實(shí) 際上未做 e.g. You should have started earlier. Shouldnt/oughtnt to + have done 不該做而做了 e.g. You shouldnt have left without

17、 telling us. (3) may/might + have done 本可以做卻沒(méi)有做（表示惋惜） e.g. You might have passed the examination.,(4) could + have done A, 本能夠做的卻沒(méi)有做，有委婉的責(zé)備語(yǔ)氣 e.g. You could have come earlier. You could have been more considerate. B, 那時(shí)可能或不可能做某事 e.g. Nobody could have foreseen all this. 這一切是誰(shuí)都預(yù)想不到的。 C, 那時(shí)“本來(lái)可以” e.g.

18、 You neednt have cooked it. We could have eaten it raw.,(5) neednt + have done 過(guò)去本不必做卻做了 C.f: didnt need to do過(guò)去沒(méi)有必要做因而也沒(méi)做 e.g. Thank you for your gift, but you neednt have bought it, for I have already have enough. He got up very late yesterday, for it was Sunday and he didnt need to go to school.,10. 與情態(tài)動(dòng)詞有關(guān)的反意疑問(wèn)句 (1) must表示“應(yīng)該，必須”時(shí)，用must構(gòu)成 e.g. We mu