如何运用“情态动词havedone”1.doc

如何运用“情态动词 + have done ”（高二22单元） 山东省沂南县第二中学(276300) 高永全情态动词 + have done 这一结构所表达的是说话人对过去已发生的行为或状态的估计、推测，或用来表达说话人对过去已发生的事情有后悔、遗憾、责备等语气。但在具体的使用过程中，不同的情态动词又各自含有不同的含义。下面就分别作一归纳总结。1、must + have + done这一结构表示说话人对过去已发生的情况或存在的状态做出的主观上确实有把握的肯定的推测，意思是“想必/准是/一定（已经）了”。如：You must have been mad to speak to the servant! 跟佣人谈，你准是疯了！Doctor Manette realized that the sister must have been very badly treated. 曼奈特医生意识到这位姐姐准是惨遭虐待。-I fell asleep on the bus before we reached our hotel. 还没到旅馆我就在车上睡着了。-It must have been a long trip. 旅途一定很长。注意：这一结构只能用于肯定句，不能用于否定句或疑问句。如果说话人要表示主观上对已发生的情况的确又把握的否定猜测，只能用cant / couldnt have done , 而不能用mustnt have done。如：-Tom must have gone to New York. 汤姆一定已去纽约了。-No，he cant. I saw him on the street just now. 不，不可能。我刚才在街上看到他。2、may / might + have done1）表示说话人对过去已发生的事情的可能的猜测。用might 比用may 所表示的可能程度要小一些。用于肯定的陈述句中，意为“或许/也许/可能（已经）了”；用在否定的陈述句中，意为“或许/也许/可能还没有”。如：He said that the key to the door might have been lost. 他说门的钥匙可能已经弄丢了。He may not have achieved all his aims. But his effort is a good one. 他可能还没达到他的全部目的，但他的努力还是不错的。注意：询问过去是否发生过某事不用may / might have done 的形式，应用can / could have done。如：Could she have lost the watch？ 她会把手表丢了吗？Could you have left your book on the bus？你会不会把书撂在公共汽车上呢？2）这一结构还用于虚拟用法，表示“本来可能”“简直可以”，但事实上并没有这样。如：She might have called for help. 她有可能会呼救的。（事实上并没有呼救）You might both have been caught and killed. 你们俩都可能被抓住杀掉。（事实上并没有被抓住杀掉）3）could / might + have done 这一结构也可以用来提出委婉的批评。如：You might / could have made greater progress. 你本来可以取得更大的进步。You might at least have answered my letter. 你至少可以给我回封信吗。3、can / could + have done1）这一结构用于各种疑问句中时，表示说话人对过去已发生的情况提出质疑，意为“可能会（已经）了吗？”。如：Where can she have gone？她会上那儿去了呢？Can she have left already？她会已经离开了吗？2）用在肯定句中时，一般只能用could 而不能用can，表示说话人对过去已发生的情况提出婉转的批评，意为“本来可以”“其实当时/那时可以的”意思。如：He could have given a better speech，but he was too nervous at that time. 他本可以讲得好一点儿,但当时他太紧张了。-I stayed at a hotel while in New York.-Oh, did you? You _ with Barbara. (NMET98 ,答案A)A. could have stayed B. could stay C. would stay D. must have stayed3）此结构用在否定的陈述中则表示说话人对过去已发生的情况主观上确有把握的否定猜测，意为“绝不可能（已经）了”。如：He cant have finished the work so soon. 他绝不可能这么快就完成了工作。Susan cant have written a report like this. 苏珊绝不可能写了这样的报告。-There were already five people in the car but they managed to take me as well. -It _a comfortable journey. (NMET95, 答案D)A. cant be B. shouldnt be C. mustnt have been D. couldnt have beenJack cant have arrived yet, otherwise he would have telephone me. 杰克绝不可能已经到了，不然他会打电话给我的。4）这一结构还用于虚拟用法，表示过去某时可能发生，但实际上去没有发生。如：You were stupid to go skiing there-you could have broken your leg. 你到那个地方去滑雪真傻，你可能会摔断腿的。（事实上并没有摔断腿）It wasnt a good idea to throw the TV out of the window-it could have hit somebody. 把电视机扔出窗外可不是个好法子-可能会砸着人的。（事实上并没有砸着人）4、can / could have been doing表示说话人对某个一直在进行的动作的推断或猜测，可用于疑问句、肯定句和否定句，意为“一直在吗？”、“可能一直在”和“不可能一直在”。如：Can they have been discussing the question all this afternoon？今天整个下午他们能一直讨论这个问题吗？The guards couldnt have been watching very carefully. 守卫不可能一直监视得很严。5、should / ought to + have done1）用于肯定句中时，表示对过去没有做某事感到遗憾，意为“本来应该的（但却没有）”。如：There was a lot of fun at yesterdays party. You ought to have come, but why didnt you? 昨天的晚会上有很多趣事，你本来应该来的，但为什么没有来呢？You are right. I should have thought of that. 你是对的，我本应该想到这一点。2）用在否定句中时，表示对过去已经做了某事的责备，意为“本来不该的（但却已经了）”。如：He ought not to have stayed up so late last night. 做完他不该睡得那么晚。The young man has made so much noise that he should not have been allowed to attend the concert. 那个青年弄出那么多噪音，真不应该允许他参加这个音乐会。6、neednt have done 其结构只有否定形式，表示对过去已经做了某事而后悔，意为“本来可以不必的（可时已经了）”。如：She neednt have attended the meeting yesterday. 她昨天本不必参加会议的。The play didnt begin until 8:00 p.m. We nee