人教版英语必修三Unit2-Grammar课件

1、Grammar Modal verbs 1. ought to表职责和义务，说话人认为“应该”否定形式：ought not to/oughtnt to 疑问句形式： 只把ought 提前e.g. 下次过马路时你应该更加小心。You ought to be more careful when you cross the road next time. 你不应该再犯这种错误了。You ought not to make this kind of mistake again.-Ought I to finish the task before ten oclock?- Yes, you ought

2、to.慢慢地进食，有助消化。 You ought to eat slowly and its good for digestion. You ought to hand in the homework on time.1. What time ought I _? Aarrived Barriving Carrive Dto arrive2. He _ speak to his mother like that. Aought not to Bdoesnt ought to Cnot ought to Dought to notb. 表推测，多指按常理的一种推测，“按理应该”e.g. Acco

3、rding to the policy the price ought to go down soon.要是他六点就出发的话，这会儿该到这里了.If he started at six, he ought to be here now. c. 多数情况下，ought to 可与should互换使用。ought to的反意疑问句用shouldnt替代。You ought to have helped him with his English, _ ?A. wont you B. ought not youC. shouldnt you D. wouldnt you 2. must和have to

4、 must的用法 1）表示主观的义务和必要,主要用于肯定句和疑问句,意思为“必须，得，要”；由must 引起的疑问句，肯定回答要用must或haveto,否定回答要用neednt或donthaveto, 意思是“不必” ； MustIfinishthetaskrightnow? 我现在必须完成这个工作吗？ Yes,youmust./Yes,youhaveto. 是的。 (No, you neednt. / No, you dont have to. 不，不必。) must的否定形式mustnt表示禁止，意思是“不能，不许”。如：You mustnt come here without perm

5、ission. 未经允许，你不能来这儿。 haveto的用法 1）must表示一种主观的需要，而haveto表示一种客观的需要，意思是“不得不”。如： I have to attend an important meeting this afternoon. 今天下午我不得不参加一个重要的会议。 Mother is out, so I have to look after the shop.妈妈不在家，因此我不得不照看商店。 2）haveto的否定形式是dont have to, 相当于neednt。如： They dont have to buy a computer at present.

6、 他们目前没有必要买电脑。【考例】The boss has given everyone a special holiday, so we _ go to work tomorrow. A. cant B. mustntC. neednt D. shouldnt【点拨】考查情态动词。根据题意, 可知这里表示“没有必要”, 故只能选C项。【考例】What do you think we can do for our aged parents?You_ do anything except to be with them and be yourself. A. dont have to B. ou

7、ghtnt toC. mustnt D. cant 【点拨】根据题意“除了和他们呆在一起做你自己外, 没有必要做任何事情。”可知这里选择dont have to表示“不必”。故选A项。3. needneednt +have done表示做了本来不必去做的事。She neednt have gone to the station yesterday.昨天她本不必到火车站去的.（昨天她去了）You neednt have bought it.你本可不必买它的。 （你买了）4. dare作情态动词多用于疑问句、否定句、条件状语从句及表示怀疑的名词性从句。 表“敢”e.g. 夜间我不敢在小树林里自己走

8、。 I dare not walk alone through the wood at night. 你怎么敢做这样的事情。 How dare you do such kind of thing?If you dare speak to me like that again, youll be sorry.如果你在敢跟我那样说话，你会后悔的。need / dare 作实义动词用，常用在肯定句中, 有人称、时态、和数的变化He needs to go there himself.He has grown up,we dont need to worry about him.Sth (sb) ne

9、ed( want, request)+ doing/ to be done The house needs cleaning/ to be cleaned. The boy needs sending to the hospital at once.I wonder how he_that to the teacher. A. dare to say B. dare saying C.not dare say D.dared sayAs it turned out to be a small house party, we _ so formally.A neednt dress B. did

10、nt have to dress upC. Might not have dressed up D. neednt have dressed upD1. I thought you _like something to read, so I have brought you some books. A. may B. might C. would D. must 2. Where is my pen? I _it. A. might lose B. would have lost C. should have lost D. must have lostII. 高考链接3. I didnt h

11、ear the phone. I _asleep. A. must be B. must have been C. should be D. should have been4. -Is John coming by train? -He should, but he _ not. He likes driving his car. A. must B. can C. need D. may5.It has been announced that candidates (候选人) _ remain in their seats until all the papers have been collected. (2002上海高考题） A. can B. will C. may D. shall6. -I heard they went skiing in the mountains last winter. -It _ true because there was little snow there. A. may not be B. wont be C. couldnt be D. mustnt be7. -There were already five people in the car, but they managed to take me as well.