1、主要情態(tài)動詞主要情態(tài)動詞vCan, couldvMay, mightvWill, would vShall, shouldvMustvHave tovOught tovNeedv dare觀察情態(tài)動詞的特性1.I can speak English.2. He can not go to the party.3. You should go to a doctor tomorrow.4. I can speak English now, but when I was 5 years old, I couldnt.1.有詞義；2.后跟動原；3.沒有人稱和數(shù)的變化；4. 部分情態(tài)動詞有時態(tài)的變化；

2、5.不單獨做謂語Modal verbs 2 ought to 表示表示“應該應該” ought to的否定式為的否定式為oughtnt to或或ought not to (1)常指常指客觀的義務或責任客觀的義務或責任. 大多數(shù)情況下可用大多數(shù)情況下可用should代替，但比代替，但比should語氣重語氣重。 We ought to stop polluting nature.你應該戒煙。你應該戒煙。You ought to quit smoking.外國人不應該加入這場內戰(zhàn)。外國人不應該加入這場內戰(zhàn)。Foreigners ought not to take part in the civil

3、 war.b. 表示勸告、建議。表示勸告、建議。 此時此時should和和ought to可通用可通用，但在，但在疑疑問句中常用問句中常用should。You should / ought to go to class right away.我們應該打開窗戶。我們應該打開窗戶。Should I open the window?我們接下來應該做什么？我們接下來應該做什么？What should we do next?You ought to help him with his English, _?A. wont you B. ought not youC. shouldnt youD. wou

4、ldnt youc. ought to可表示推測，意為可表示推測，意為“按道按道理應該理應該”。（與。（與should用法相同）用法相同）Try to translate:He ought to / should be home by now. He works very hard, he ought to get good grades in the exam. Can you give advice?做一些運動做一些運動 You ought to/should do some sports. As a student, you ought to hand in the homework o

5、n time.按時交作業(yè)按時交作業(yè)have to 的用法的用法 1) have to 意思是意思是“不得不，必不得不，必須須”。 如：如： 今天下午我不得不參加一個重要今天下午我不得不參加一個重要的會議。的會議。I have to attend an important meeting this afternoon.2) have to 的否定形式是的否定形式是dont have to,意為意為“不不必必”。 表示沒有義務或者沒有必要做某事。表示沒有義務或者沒有必要做某事。如：他們現(xiàn)在沒有必要買電腦。如：他們現(xiàn)在沒有必要買電腦。 They dont have to buy a computer

6、 now.區(qū)分：區(qū)分：must表示一種主觀的需要，而表示一種主觀的需要，而have to表示一種客觀的需要表示一種客觀的需要（1）Mother is out, so I look after the shop.（2）I want to enter a top university, so I study very hard.【考例【考例】The boss has given everyone a special holiday, so we _ go to work tomorrow. (上海上海 2007春春)A. cant B. mustntC. dont have to D. shoul

7、dnt【點撥【點撥】考查情態(tài)動詞。根據(jù)題意考查情態(tài)動詞。根據(jù)題意, 可知可知這里表示這里表示“沒有必要沒有必要”, 故只能選故只能選C項。項。【考例【考例】What do you think we can do for our aged parents?You _ do anything except to be with them and be yourself. (重慶重慶 2007)A. dont have to B. oughtnt toC. mustnt D. cant 【點撥【點撥】根據(jù)題意根據(jù)題意“除了和他們呆在一除了和他們呆在一起做你自己外起做你自己外, 沒有必要做任何事情。沒

8、有必要做任何事情?！笨芍@里選擇可知這里選擇dont have to表示表示“不必不必”。故選故選A項。項。3.need(情態(tài)動詞情態(tài)動詞/實義動詞）實義動詞）(1)need作情態(tài)動詞時作情態(tài)動詞時, 意為意為“需要，有必要需要，有必要”后跟動詞原形，多用于疑后跟動詞原形，多用于疑問句問句,否定句或條件句中。否定句或條件句中。 You neednt go to work today. Need I finish the work today? Yes, you must/ have to. / No, you neednt. (2)need還可做實義動詞，后跟to do 動詞不定式.和其他實義

9、動詞一樣，可用于各種句式，有時態(tài)，人稱和數(shù)的變化，構成否定和疑問句時要借助于助動詞do.You need to be careful.否定句You dont need to be careful.他需要休息一下。He needs to have a rest.Translation我的房間需要打掃。My room needs to be cleaned.need作“需要”講時，其后跟不定式的被動形式相當于跟v-ing的主動形式。want 與require做需要講時，也有這種用法。=My room needs cleaning.我的自行車需要修理。My bike needs to be repa

10、ired.=My bike needs repairing. 注意對注意對need問句的回答問句的回答: -Need I finish the work today? -Yes, _. No, _. No, _.you must/have toyou needntyou dont have toneednt 對其它情態(tài)動詞的回答對其它情態(tài)動詞的回答:-Shall I tell John about it?-No, you _.-No, you _ . -Must we do it now? -No, you _.-No, you _ .needntdont have toneedntdont

11、have to4. dare的用法a.dare既可作情態(tài)動詞也可做實義動詞。 做情態(tài)動詞時多用于疑問句，否定句，條件狀語從句以及表示懷疑的名詞性從句中，意為“敢?！?。I dare not /darent walk through the forest at night.變?yōu)橐话阋蓡柧洌篵. dare 做實義動詞時，后跟to do 動詞不定式，在否定句中不定式符號to也可以省略。和其他實義動詞一樣，可用于各種句式，有時態(tài)，人稱和數(shù)的變化。He dared to jump over the stream.He will dare to face any danger.I have never da

12、red (to) go back to take a look.He doesnt dare (to) walk at night. 表示否定的情態(tài)動詞的用法表示否定的情態(tài)動詞的用法:mustntneednt = (dont have to )cantmay not shouldnt ( = ought not to )部分情態(tài)動詞的否定式是情態(tài)動詞中的部分情態(tài)動詞的否定式是情態(tài)動詞中的考點之一?？键c之一。（一）表對過去發(fā)生的事情的推測（一）表對過去發(fā)生的事情的推測 may/might have done可能已做可能已做 must have done 一定已做（肯定句中）一定已做（肯定句中）

13、cant have done（過去）不可能做了。（過去）不可能做了。-Where is my pen?- I must have lost it.The light in his room is still on, so he cant have gone to bed.Our headmaster might have known what you did yesterday.情態(tài)動詞情態(tài)動詞+have done結構的用法結構的用法(二二)could have done指指“本來能做而實際未做本來能做而實際未做”或或“可能已經做過某可能已經做過某事事”，表達遺憾的感情色彩，表達遺憾的感情色彩

14、 You could at least have sent(郵寄郵寄) five cards.（三）（三） need have done 表示本來需要做某事而實際未做表示本來需要做某事而實際未做”neednt have done表示過去本來沒有必要做表示過去本來沒有必要做 某某事，但事實上卻做了。事，但事實上卻做了。 There was plenty of time. She neednt have hurried.（四）四）should /ought to have done本來應做而未做，表達遺憾、責備等感情色彩本來應做而未做，表達遺憾、責備等感情色彩 You should/ought t

15、o have made the decision a week ago. I shouldnt have made such a foolish mistake. I told Sally how to get there, but perhaps I should have written it out for her.I was really anxious about you, you shouldnt have left home without a word.1. I thought you _ like something to read, so I have brought yo

16、u some books. A. can B. might C. will D. must 2. I cant find my pen everywhere. I _ it. A. might lose B. would have lost C. should have lost D. must have lost高考鏈接高考鏈接3. I didnt hear the phone. I _ asleep. A. must be B. must have been C. should be D. should have been4. -I heard they went skiing in th

17、e mountains last winter. -It _ true because there was little snow there. (2002北京北京高考題高考題) A. may not be B. wont be C. couldnt be D. mustnt be5. Its nearly seven oclock . Jack _ be here now. A. will B. need C. should D. can6. -Could I borrow your dictionary?Yes, of course you_.A. mightB. will C. canD

18、. should7. _you mind my smoking here?A. ShouldB Could C. MightD. Would8. -Is John coming by train? -He should, but he _ not. He likes driving his car. (2002高考題）高考題） A. must B. can C. need D. may9. It has been announced that candidates (應試者，考生應試者，考生) _ remain in their seats until all the papers have

19、been collected. (2002上海上海高考題）高考題） A. can B. will C. may D. shall 1 Children under 12 years in that country _ be under adult supervision when in a public library. (2007 上海）上海） A. must B. may C. can D. need 2 Do you know where David is? I couldnt find him anywhere. (2005湖北湖北) Well. He _have gone farhi

20、s coats still here.Ashouldnt Bmustnt C. cant Dwouldnt 3. The weather turned out to be fine yesterday. I _ the trouble to carry my umbrella with me. (2006 江西）江西） A should have taken B could have taken C neednt have taken D mustnt have taken4 Must he come to sign this paper himself? Yes, he . (2006廣東廣

21、東)A. need B. must C. may D. will5. Theres light on they_ be at home. (2006 全國全國I)A. cant B. mustC. might D. shall 6. You cant imagine that a well-behaved gentleman _ be so rude to a lady. (2001上海上海) A. might B. need C. should D. would Deal with the following situations using as many modal verbs as you can.Give your advice:vYour little sister asks you how