大学英语 情态动词2[精选].ppt

Ought to表示义务或责任，提醒某人义务或提出劝告，指出一个正确、明智的行为。 Must强调主观愿望，涉及说话人的权威 Have to表示由某种情况或环境所迫而不得不做的事 Should和ought to完全相同，但ought to语气更重。 You ought to respect the old You must do it at once We’ll have to reconsider the matter We should (ought to) do more for the country 1.表示征求意见或请求指示 Shall we meet in the evening? How shall I start the machine? 2.表示意图、意志、允诺或命令等，但shall所表示的意志是说话人的意志，并非句子主语的意志 I shall give you a lot of money Each citizen shall carry his identification card when travelling. She shall get this paper in the evening He shall get what he deserves 1. 用于疑问句或感叹句，表示“推断” How should I know? Why should you be worrying? 2. 用在I’m surprised, it worries me, it’s a pity, it’s unthinkable等结构后面的句子中表示惊讶、忧虑、惋惜、欢欣等情绪。 I’m surprised that he should eat so little every day. It’s a pity that she should fail in the entrance examination. 情态动词和助动词一样，都是辅助性的动词，用来帮助构成不同的时态和语态， 表示说话者的某种情态，没有人称和数的变化 may might can could shall should will would Must 无变化 1. 表示请求 Will you give her the letter? Would you please tell me your telephone number? 2.表示习惯或倾向，与used to 进行对比 Scarf used to be heavy smoker Father used not to be so forgetful 2. Would强调过去某种特定情况下的动作，是完全过去的事情，与现在没有联系。 She used to get up at six in the morning She would get up at six in the morning Man used to think that the earth was flat Man would think that the earth was flat In those days, whenever I had difficulties, I____ Mr. Shen for help. A. Used to go to B. Was used to go to C. Would go to D. Used to going to He_____up at five, but now he gets up at six. A. Used to getting B. Would get C. Was used to get D. Used to get 3.表示推测 It will be Mr. Wang knocking at the door. It would be about ten o’clock when he left home They____in New York by now. A. will arrive B. will be arriving C. will have arrived D. are arriving 4. 表示命令、强迫 All will arrive before 7:45 5. 表示意愿或者固执地坚持。 She won’t lend me the money The window won’t open 6.表示能力（拟人化） The hall will seat