情态动词情态动词modal verbs常用的情态动词常用的情态动词can （could）may（might）shall（should）will （would） must（must）dare （dared）need （need）have to ought to be able toused tohad better表示说话人的语气或情绪情态动词有一定的意义,但不完整不能单独作谓语动词，必须和动词原形一起构成谓语 无人称和数的变化在情态动词的使用中在情态动词的使用中, , 我们要注意以下考点我们要注意以下考点: :1. 表示能力、许可的情态动词的用法。表示能力、许可的情态动词的用法。2. 表示否定的情态动词的用法。表示否定的情态动词的用法。3. shall 和和 will 的多种意义的区别。的多种意义的区别。4. 情态动词短语的使用。情态动词短语的使用。5.情态动词表示推测的使用。情态动词表示推测的使用。6.虚拟语气中情态动词的使用。虚拟语气中情态动词的使用。 表示能力表示能力: can, could, be able to *be able to 能用于能用于各种时态各种时态。 can / could 只能表示只能表示现在现在或或过去过去的能力。的能力。 *was / were able to : “设法做成某事设法做成某事” 相当于相当于 managed to do sth. succeeded in doing sth.。1. 1. 表示能力、许可的情态动词的用法。表示能力、许可的情态动词的用法。1. A computer _ think for itself; it must be told what to do. A. cant B. couldnt C. may not D. might not2. The fire spread through the hotel very quickly but everyone _ get out. A. had to B. would C. could D. was able toA D 3. They will _ run this machine on theirown in three months.A.can B. could C. may D. be able to4. That big cinema _ seat 2,000 people.A. can B. should C. ought to D. is able toD A 表示许可表示许可: may / might, can / could * might, could 比较比较委婉委婉, 一般多用于一般多用于疑问句疑问句.* can, may 表达的语言比较随便表达的语言比较随便.* 在以在以could, might 表示表示征询对方意见征询对方意见 或或表示请求表示请求时，回答应相应使用时，回答应相应使用can, may.5. Could I borrow your dictionary? Yes, of course you _.A. might B. will C. can D. should6. Might I watch TV after supper? Yes, you _.A. may B. must C. might D. canC A 2. 2. 表示否定的情态动词的用法表示否定的情态动词的用法: :部分情态动词的否定式是情态动词中的考点之一部分情态动词的否定式是情态动词中的考点之一 mustnt neednt cant may not shouldnt 不准不准, 禁止禁止 没必要没必要 ( = dont have to )不能不能; 不可能不可能不可以不可以; 可能不可能不不应该不应该 ( = ought not to )7. You _ return the book now. You can keep it till next week if you like.A.cant B. mustnt C. neednt D. may not8. Johnny, you _ play with the knife, you _ hurt yourself. A. wont ; cant B. mustnt ; may C. shouldnt ; must D. cant ; shouldntC B 9. -Will you stay for lunch? -Sorry, _. My brother is coming to see me. A. I mustnt B. I cant C. I neednt D. I wont10. -May I pick a flower in the garden? - _. A. No, you neednt B. Not, please. C. No, you mustnt D. No, you wontB C 情态动词：情态动词：shall, will 的多种意义的多种意义: shall / will+ 动词原形动词原形: * shall 可表示必须、命令、可表示必须、命令、 警告或征询意见警告或征询意见. * will 可表示意愿、常出现的动作、在疑问句可表示意愿、常出现的动作、在疑问句 中表示请求和建议中表示请求和建议.* 均可表示将来。均可表示将来。 过去时为过去时为 should, would.3. shall用在主语是第一和第三人称的疑问句中表示用在主语是第一和第三人称的疑问句中表示征求对方的允诺；征求对方的允诺；Shall I open the window?Shall he come in or wait outside?will用在主语是第二人称的疑问句中用在主语是第二人称的疑问句中,表示表示“请求请求”Would you pass the salt, please?Will you please pass the salt?will用于主语是各人称的陈述句中用于主语是各人称的陈述句中,表示表示“意愿、倾意愿、倾向向”-The phone is ringing.- Ill get it.11. He _ be punished if he disobeys. 如果他不服从如果他不服从, 就要受到惩罚就要受到惩罚.12. We are not going to quarrel at all if you _ only let me speak. 只要你让我说话只要你让我说话, 我们根本就不会吵架我们根本就不会吵架.13. -Sir, _ he go or stay? -Let him go. A. will B. shall C. might D. couldshallwillB 14. The door _ open. 这门经常打不开这门经常打不开.15. Ronald _ stay in his small garden for a long time every day in the past. A. could B. might C. should D. would16. You _ have the book after I read it. 我看完以后一定把这本书给你我看完以后一定把这本书给你.wontD shall4. 4. 情态动词短语的使用情态动词短语的使用: :would like to dowould rather dowould rather + sb.+ did sth.would prefer to do.had better do.宁愿宁愿改错改错:1. Would you like having some tea?2. Id prefer going to the lecture this evening.3. Id rather you to go to the meeting.4. He would rather to die than to give in.5. Youd better to have your hair cut today.Would you like to have some tea?Id prefer to go to . you went to .He would rather die than give in.Youd better have .5.5.表示推测表示推测情态动词的重要用法情态动词的重要用法. .1. You must be Mr Smith-I was told to expect you here.2. He must have known what we wanted.3. We may have read the same report.4. He cant have slept through all that noise.5. Theres someone outside-who can it be?6. What can they be doing?7. These pills might help to cure your disease.8. You could be right, I suppose.表示推测表示推测情态动词的重要用法情态动词的重要用法. .肯定的推测肯定的推测可能的推测可能的推测否定的推测否定的推测疑问的推测疑问的推测must 对将来对将来 对现在对现在 对过去对过去情态动词情态动词may, mightcould cant, couldntcan, could + V. + V. + have done常见常见must be + be doing + V. + V. + have done + be doing 可以用可以用not表示表示“可能不可能不” +V. + V. + have done + be doing+ V. + V. + have done + be doing高考考题高考考题:1. 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 lost3. I didnt hear the phone. I _asleep. A. must be B. must have been C. should be D. should have beenBD B 4. -There were already five people in the car, but they managed to take me as well. -It _a comfortable journey A. cant be B. shouldnt be C. mustnt have been D. couldnt have been 5. Its nearly seven oclock . Jack _be here at any moment. A. must B. need C. should D. could D C 不同的不同的“肯定肯定”程度可按下列层次排列：程度可按下列层次排列： He is at home. (事实事实) He must be at home.（非常肯定的推断）（非常肯定的推断） He could be at home.（很可能）（很可能） He ought to be at home.（很可能）（很可能） He may be at home.（仅仅可能而已）（仅仅可能而已） He might be at home.（或许（或许, 非常不确定）非常不确定） He might not be at home.（也许不在家）（也许不在家）He may not be at home. （比（比might可能可能） He couldnt be at home.（很可能不在家）（很可能不在家） He cant be at home.（一定不在家）（一定不在家）He isnt at home.（事实）（事实） 6. 6. 用于虚拟语气的情态动词用于虚拟语气的情态动词: :should/ ought to have done shouldnt / oughtnt to have done might / could have doneneednt have done本应该做本应该做（但事实没做）（但事实没做） 本来不应该做本来不应该做（但事实却做了）（但事实却做了）本来可以做本来可以做（但事实没这样做）（但事实没这样做）本来不需要做本来不需要做（但事实却做了）（但事实却做了）1. I was really anxious about you. You _ home without a word. A. mustnt leave B. shouldnt have left C. couldnt have left D. neednt leave2. There was a lot of fun at yesterdays party. You _ come, but why didnt you?A. must have B. should C. need have D. ought to haveBD3.I stayed at a hotel while in New York. -Oh, did you? You _ with Barbara.A.could have stayed B.could stayC.would stay D.must have stayed4.I told Sally how to get here, but perhaps I _ for her.A.had to write it out B. must have written it outC. should have written it out D. ought to write it outAC