语法复习：情态动词课件.ppt

1.can表示能力 I can speak English while he can’t . 2.表示允许 Can I sit here? 3.表示可能性 This can’t be true. What can it mean? They can’t have been to Africa. may1）表示允许，征求别人意见 ---May I come in?---Yes,please. 2)表示判断和猜测 He may come,but I am not sure. This may be true or may not be true. might语气婉转，或不是很肯定的猜测 Don’t throw the empty bottle out of the window.You might hurt someone. 1）must表示“必须” You must finish your homework at once. You mustn’t play with fire. You mustn’t play football on the road. 2)表示猜测，语气很肯定 She must be hungry. He looked worried.He must have lost his way. It’s so wet on the ground that it must have rained heavily last night,____________? 情态动词的否定式 can’t:不能；不可能 may not:可能不 mustn’t:不准；不许；禁止 needn’t:不必 daren’t:不敢 won’t:不愿意，就是不 shan’t:决不 shouldn’t:不该 1.--Excuse me, but I want to use your computer to type a report. --You ____ have my computer if you don’t take care of it. A. shan’t B. might not C. needn’t D. shouldn’t A 2. ---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 B 3. With so much work on hand, you ____to see the game last night. A. mustn’t go B. could have gone C. shouldn’t go D. shouldn’t have gone D 1. A computer ______ think for itself; it must be told what to do. A. can’t B. couldn’t C. may not D. might not 2. The fire spread through the hotel very quickly but everyone ______ get out. A. had to B. would C. could D. was able to A D 3. They will ______ run this machine on their own in three months. A. can B. could C. may D. be able to 4. That big cinema ______ seat 2,000 people. A. can B. should C. ought to D. is able to D A 表示许可: may / might, can / could * might, could 比较委婉, 一般多用于疑问句. * can, may 表达的语言比较随便. *