情态动词 hao.ppt

* 情态动词表说话人的某种感情 或语气，对某一动作或状态的 某种态度。表示“需要、可以、 必须、应当”等。 情态动词 ( modal verbs) 1) Some of us can use the computer now, but we couldn’t last year. 2) The new-built theatre can seat 1500 people. 3) Can she be in the computer center? 4) I though what he said could not be true. 5) Can/Could I use your dictionary? 6) Could you lend me a hand? 1.表能力 3. 表示“请求” “允许”(表请求时，口语中常用 could 代替 can 使语气更委婉，回答时用can) 2. 表示推测，意为“可能”“或许”，用于疑问句或否定句 1. can 与could 4. 表示“许可”，可与may 换用。 You can go home now. 5. can 用于疑问句或否定句中时，表惊异、 不相信等，意思是“可能、能够”。 How can you say that you really understand the whole Story if you have covered only part of the article? 6. can’t/ couldn’t +have + done 表示对过去 情况的否定推测 Susan can’t have written a report like this. 7. could + have + done 表示对过去能做而 未做的事情感到惋惜，遗憾 It’s a pity. Your class could have got the first prize. Michael ____ be a policeman, for he’s much too short. A. needn’t B. can’t C. should D. may 2. Mr. Bush is on time for everything. How ____ it be that he was late for the opening ceremony? A. can B. should C. may D. must 3. ---- I stayed at a hotel while in New York. ---- Oh, did you? You ____ with Barbara. A. could have stayed B. could stay C. would stay D. must have stayed My sister met him at the Grand Theater yesterday afternoon, so he ____ your lecture. A. couldn’t have attended B. needn’t have attended C. mustn’t have attended D. shouldn’t have attended B A A A 2. may 与might 1. 表示“许可”或“请求”，有“可以”的意思，口语中 常用 might 代 may ,表示委婉语气。 否定回答时用“must not”表“禁止，阻止”， Eg: 1)--- May I watch TV after supper? --- Yes, you may. / No, you mustn’t. 2. 表示可能性。 意为“或许，可能” might 比 may 可能性小。 Eg: 1) It might be true. 2) They may be in the library now. 3) Today is Sunday. She may not be in her office now