语法系列2 情态动词.ppt

* 情态动词 情态动词 情态动词主要有：can, could, may, might, shall, should, will, would, must, need, dare, dared, ought to等。 用法: 1.表示猜测。 He is at home now. (陈述句，一般现在时） He must be at home now. He should be at home now. He may/might be at home now. He can’t/couldn’t be at home now. He may/might not be at home now. He was at home last night. (陈述句，一般过去时） He must have been at home last night. He may/might have been at home last night. He can’t/couldn’t have been at home last night. He may/might not have been at home last night. Is he at home now? (疑问句) Can/Could he be at home now? 2.表示与过去事实相反的虚拟情况。 should have done 本来应该做而没有做 shouldn’t have done 本来不应该做而做了 could have done 本来可以做而没有做 needn’t have done 本来不必做而做了 3.某些情态动词的特殊用法。 ① would do可以表示过去的习惯性动作。 eg) He would take a walk along the river after supper when he lived in his hometown. ②should可以表示“万一”。 eg) If it should rain tomorrow, we will have to stay at home. ③ must可以表示“偏要”。 eg) Tom, must you play the piano at such a late hour? ④shall在疑问句中用于第一或第三人称时，可以用来征求对方意见。在陈述句中用于第二或第三人称时，可以表示警告、命令、允诺等含义。 eg) Shall I copy the letter for you? You shall get punished if you make any trouble again. 情态动词练习一（2008年全国各地高考试题摘录） 1. Liza ______ well not want to go on the trip --- she hates traveling.（2008全国卷Ⅱ） A. will B. can C. must D. may 2. John promised his doctor he ______ not smoke, and he has never smoked ever since.（2008北京卷） A. might B. should C. could D. would D D 情态动词练习一（2008年全国各地高考试题摘录） 3. She ______ have left school, for her bike is still here. （2008天津卷） A. can’t B. wouldn’t C. shouldn’t D. needn’t 4. What a pity! Considering his ability and experience, he ______ better.（2008江西卷） A. need have done B. must have done C. can have done D. might have done A D 情态动词练习一（2008年全国各地高考试题摘录） 5. You don’t have to know the name of the author to find a book. You ______ find the book by the title.（2008湖南卷） A. must B. need C. can D. would 6. ---What sort of house do you