高中英语语法：情态动词

1、PAGE PAGE - 3 -Modal Verbs、情态动词概述 1表示能力 He can carry the heavy box. 2表示职责 ought to / should, have to 和must的语气由弱到强 You must work as hard as possible. 3表示确定 might表示非常不肯定，my, could, should, ought to, will语气逐渐增强，must则表示几乎完全肯定 You might beat him in the competition. 4表示许可 在非正式场合或英语口语中，常用can或could表示许可，coul

2、d更有礼貌。而在正式场合或书面语中，则常用may或might表示许可，might更正式。 You can go out to play after you finish your homework. 5表示提出要求 在从非正式场合至正式场合的过渡中，依次使用will, can, could和would Can you help me with my English? 6表示给出建议 Shall we do some shopping tomorrow?、情态动词的用法 1can / could 表示能力 He could speak English when he was four years

3、 old.表示请求或允许 表示委婉地请求或陈述看法时，口语中多用could, 但回答时仍然用can You cannot park your car here. Could I see your driving license? Of course you can.表示推测 He cant be at home now. 2may / might 表示征求对方意见或允许 might比may语气更加婉转一些，是比较正式的用法，口语中使用can比较普遍 You may come if you wish. He asked if he might go home.表示推测 He may come v

4、ery soon. may well 很可能，极有可能 might /may as well 不妨做某事 may not 3must表示“必须”，mustnt表示“禁止” You must hand in your composition today. You mustnt park here! Its an emergency exit. (重庆2010)表示推测 He must be ill. He looks so pale.用must提问时的回答 Must I finish my homework today? No, you neednt. / Yes, you must.must表

5、推测时的反意疑问句不考虑must They must be playing basketball, arent they? You must have studied English for years, havent you? He must have finished it, hasnt he?He must have finished it yesterday, didnt he? must非得，一定要 May I park in this amusement park? If you must, choose a place where there are few children.

6、Must you worry her with questions, just when she is busy cooking dinner? 4should / ought to表示应该 You should complete your experiment in time.表示推测 They should be at home by now, I think. 到家 情态动词+have done 对过去事实的一种猜测和判断 5will / would表示意愿 I would go there with you.表示习惯和倾向性 This window wont open.这扇窗户经常打不

7、开。 When he was a child, he would go skiing.*will如在疑问句中表示征求对方意见，则和第二人称连用 6shall征求对方意见 第一、三人称 What shall we do this evening? Shall he come in?表示命令，警告，允诺，威胁 第二、三人称 Every competitor shall arrive there in time. If you behave well, you shall get a present.You shall fail to pass the entrance examination if you dont study harder. The school rules state that no child shall be allowed out of the school during the day, unless accompanied by an adult. 7need, dare 通常用于疑问句和否定句 You neednt go training if you feel tired. You dont need to go tra