1、 情态动词 + have done 重点1. Something may have happened to her. 她可能发生了什么事情。 She might have had an accident. 她或许遭受了意外. So she must have taken that too. 因此，她肯定把它也带走了。 1) 这三句话都用了“情态动词不定式的完成时 ”，表示对发生过的事作某种猜测、推测。(1) must have done 可用来对某件过去的事情作肯定推测，表示“一定已经，想必已经”做过某事，用于肯定的陈述句中。否定句中用 cant have done。 She must hav
2、e received the parcel, I sent it by registered post. 她一定已经收到包裹了，我是用挂号寄的。 (2) may have done, might have done, could have done “可能做过某事” ，就语气而言 could have done 所表的可能性更小些。 He may / might / could have left by nine. 他可能于九点前已离去。 (3) should have done / ought to have done 表示“本该做某事 ”但实际未做。 I should / ought to
3、 have left London before nine but I didnt. 我本该在九点以前离开伦敦，但是我没有。 (4) shouldnt have done / oughtnt to have done 表示“本不该做事” ，但实际上又做了。 He shouldnt / oughtnt to have left London before nine but he did. 他本不该在九点前离开伦敦，但是他离开了。 (5) cant / couldnt have done 表否定推测， “不可能做过某事 ”。 She cant / couldnt have gone to bed,
4、 for the light in her room is still on. 她不可能上床睡觉了，因为她房间的灯还亮着。 (6) could have done 可表示客观上“本来能做某事但实际上没做” 。 He could have finished the work in time but he didnt work hard. 他本来可以按时干完活的，但他没有卖力。 (7) neednt have done 表示客观上“本不必做某事但实际上又做了” 。 I neednt have gone to the office yesterday (but I went there). 昨天我没
5、必要去办公室（但我却去了） 。 (8) might have done 还可表示过去 “本可能发生但实际上没有发生的动作” 。用于表示说话人对已发生的事提出批评或意见。 He might have given more help, even though he was very busy. 即使他很忙，也可以多帮点忙。 情态动词 + 动词完成式即“ 情态动词 + 动词完成式即“情态动词 + have + done”，表示对过去行为或动作进行推测、评论或判断。这个结构是近几年高考情态动词的重点和难点。一、在虚拟语气中的用法 1. should have done 表示“过去本应该做某事却未做。
6、”其否定结构 shouldnt have done 表示 “过去本不该做某事却做了。 ” 2. ought to have done 表示“过去本应该做某事却未做。 ”其否定结构 oughtnt to have done 表示“过去本不该做某事却做了。 ” 3. need have done 表示“过去本有必要做某事却未做。 ”其否定结构 neednt have done 表示“过去本没必要做某事却做了。 ” 4. could (不能用 can) have done 表示“过去本能够做某事却未做。 ”注意：其否定形式 couldnt have done 没有虚拟语气的用法，couldnt ha
7、ve done 只能表推测，相当于 cant have done，意为：“过去不可能做了某事。 ” 5. might (不能用 may) have done 表示“过去本可以做某事却未做。 ” 注意：其否定形式 might not have done 没有虚拟语气的用法，might not have done 只能表推测，相当于 may not have done，意为： “过去可能没有做某事。 ” 二、表推测的用法 1. must have done 表示对过去某事的肯定猜测，译为：过去肯定做了某事。不存在 mustnt have done 的形式。其否定或疑问形式须用 can(could)
8、 来表示. 例如： Since the road is wet, it must have rained last night. 既然路是湿的，那昨天晚上肯定下雨了。 He cant have missed the way. I drew him a map. 他不可能迷路。我（当时）给他画了张图。 “The dictionary has disappeared. Who could have taken it?”词典不见了， （过去）谁可能把它拿走了？ 2. may / might have done may / might have done 表示“过去可能做了某事” 。may 比 mig
9、ht 表示的可能性在说话人看来稍大些。may/might not have done 表示“过去可能没有做某事。 ”例如： I cant find my keys. I may / might have left them at the school yesterday. 我找不到我的钥匙了。我可能昨天把他们落在学校了。John may/might not have passed the exam; he looks very sad.约翰可能没有通过考试。他看起来很忧伤。注意：may/might have done 表推测不能用于疑问句中。 3. can/could have done 表推
10、测一般用在否定句和疑问句中，表示不相信或怀疑的态度。 Can/Could he have passed the exam?他可能通过了考试吗？ I think that he couldnt/cant have gone abroad. I saw him just now.我认为他不可能出国了。我刚才还看见他了。 注：表示推测过去某动作发生的可能性时，就表示的可能性程度而言，must 最大，could 其次，may 更次之， might 最小。例如： “I wonder how Tom knew about your past.” “我想知道汤姆是怎么知道你的过去的。 ”“He must /
11、 could / may / might have heard of it from Mary.” “他肯定/很可能/可能/兴许（没准儿）已从玛丽那儿听说此事了。 ”“情态动词 have done”考点解析“情态动词have done”结构是重要考点，也是较难掌握的语法项目之一，为了帮助同学们更好地掌握使用这一考点，下面结合近年高考试题谈谈其主要用法。考点之一：在虚拟条件句中，如果表示与过去事实相反的情况，从句中用过去完成时，而主句中则用“情态动词现在完成时”，即：would/ could/ should/ might have done。例如：If they had finished the
12、 work on time, they would have been praised by the manager.If you had worked hard, you could have passed the examination.考题分析：1. If it _ for the snow, we _ the mountain yesterday. A. were not; could have climbed B. were not; couldC. had not been; could have climbed D. had not been; could climb2. - I
13、 stayed at a hotel while in New York. - Oh, did you? You _ with Barbara. A. could have stay B. could stay C. would stay D. must have stay3. Yesterday Jane walked away for discussion, otherwise, she _ something she would regret later.A. had said B. said C. might say D. might have said答案简析：1. 根据信息词 ye
14、sterday 可以判断该句是表示与过去事实相反的虚拟条件句，从句中应该用“情态动词现在完成时”，故答案选 C。2. 本句是一个含蓄虚拟条件句，意思是：If you hadnt stay at a hotel while in New York, you could have stayed with Barbara. 表达了与过去事实相反的情况，答案选 A。3. 本句考查的也是含蓄虚拟语气，意思是：如果她参加了讨论，她可能会说出一些后来令她后悔的话。表达了与过去事实相反的情况，故答案选 D。考点之二：must have done 表示对过去已经发生过的情况的肯定推测判断，语气较强，意思是“一定
15、、肯定”。其否定形式分别用 cant/ couldnt和 can/ could。例如：It must have rained last night, for the ground is wet this morning.昨天晚上一定是下雨了，因为今晨地面是潮湿的。She didnt attend the lesson yesterday. She must have been ill.她昨天没有上课，她一定是生病了。1. Must have done 语气极强，表示非常肯定，一定做了某事，基本只用肯定句巩固练习.He _ have completed his work, otherwise,
16、he wouldnt be enjoying himself by the seaside. A. should B. must C. wouldnt D. cantThis cake is very sweet. You _ a lot of sugar in it. . Should put B. could have put C. might put D. must have putI was on the highway when this car went past followed by a police car. They _ at least 150 kilometers an
17、 hour. A. should have been doing B. must have been doingC. could have done D. would have doneI didnt hear the phone. I _ asleep. A. must be B. must have been C. should be D. should have been2. may/ might have done 也用于对已经发生过的情况的肯定推测判断，但语气稍弱，意思是“可能，或许”。例如：She didnt get there in time. She may have miss
18、ed the bus.她没能及时到达那儿。她可能没赶上汽车。He didnt come to school today. He might have been ill.他今天没来上课，他可能病了。巩固练习：1. Sorry, Im late. I _ have turned off the alarm clock and gone back to sleep again.(A. might B. should C. can D. will2. The window was broken. Tom _ have done that, for he was a little naughty.A.
19、could B. might C. should D. ought to3. Yesterday, Jane walked away from the discussion. Otherwise, she _ something she would regret later. A. had said B. said C. might say D. might have said 答案简析：这三句表达的都是对过去已经发生过的情况的推测判断，意思是“可能、或许”，应该用 may/might have done 结构。答案分别选 ABD。3. 如果对过去情况推测判断的句子是疑问句和否定句，只能用 c
20、ancould 和cant,couldnt。例如：He cant have gone abroad; I saw him an hour ago.他不可能去国外，我一个小时前还见到他呢。- Can he have passed the exam? - No, he cant have. He didnt work hard.他通过考试了吗？不，他不可能通过考试。他学习不努力。巩固练习：1. - There were already five people in the car but they managed to take me as well.- It _ a comfortable jo
21、urney. A. cant be B. shouldnt be C. mustnt have been D. couldnt have been2. My sister met him at the Grand Theatre yesterday, so he _ your lecture. A. couldnt have attended B. neednt have attendedC. mustnt have attended D. shouldnt have attended3. My English-Chinese dictionary has disappeared. Who _
22、 have taken it? A. should B. must C. could D. would4. I didnt see her in the meeting-room this morning. She _ at the meeting. (1995 上海)A. mustnt have spoken B. shouldnt have spokenC. neednt have spoken D. couldnt have spoken答案简析：1、根据 They were already five people in the car, but they managed to take
23、 me as well.一句中的时态，应该是对过去情况的推测判断，因为车上已经有 5 位人了，在带上我一个，可以断定这一定是一次不舒适的旅行。所以，本句表达的是对过去否定的推测判断，应该用 cant/ could have done 来表达。故答案选 D。2、根据句意“我妹妹昨天在大剧院见过他”，所以，一定是对过去已经发生的否定的判断，答案选 A。3、本句表达的是对过去发生过的情况的疑问，所以应该用 could have done，答案选 C。4、本句表达的是过去已发生情况否定的推测判断，应该用 couldnt have done，故答案选 D。4. 含有 must/ may/ might 表
24、示对过去情况推测判断的句子，如果变成反意疑问句，反意疑问句中动词应与情态动词 must 等后的动词形式保持一致，用一般过去时或现在完成时。例如：He must have been living here for years, hasnt he?他一定是在这儿住了好几年了，是吗？You cant have slept well last night, did you?你昨天晚上没睡好，是不是？巩固练习：1: Great changes must have taken place in the village in the past few years, _ they?A. mustnt B. h
25、avent they C. cant D. didnt2. He must have lived a happy a few years ago, _ he?A. didnt B. hasnt C. mustnt D. cant答案简析：1. 含有 must 表示推测判断的句子，其反意疑问句的动词形式应与 must 后动词时态保持一致。可以理解成如果不表示推测判断，该句应该说成：Great changes have taken place in the village in the past few year. 变成反意疑问句后应该说成：Great changes have take plac
26、e in the past few years, havent they? 所以，该题选 B。2. 本句中 must 后的动词形式应为 did，所以，反意疑问句的动词应为 didnt。故答案选 A。 5. should/ ought to have done 表示“本来应该做的，而实际上没有做的事情”，其否定形式则表示“已经做了不该做的事情”，含有责备的意思。例如：The flowers have died. I should have watered them often.这些花儿都死了。我本来应该常给他们浇水的。（其实没浇水）You ought not to have told them
27、the truth.你本不应该告诉他们真相的。（其实你告诉他们了）巩固练习：1. 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 have2. Oh, I am not feeling well in the stomach, I _ so much fried chicken just now. A. shouldnt eat B. mustnt have eaten C. shouldnt ha
28、ve eaten D. mustnt eat3. I was really anxious about you. You _ home without a word. (NMET 2001)A. mustnt leave B. shouldnt have left C. couldnt have left D. neednt leave - Ill tell Mary about her new job tomorrow.-You _ her last week. A. ought to tell B. would have told C. must tell D. should have t
29、oldMr. White _ at 8:30 for the meeting, but he didnt show up. 4. Mr. White _ at 8:30 for the meeting, but he didnt show up.A. should have arrived B. should arriveC. should have had arrived D. should be arriving答案简析：1、 本句的意思是：昨天的聚会很有意思，你本来应该来的，可你为什么没来？表示“本应该做，而实际上没有做的事情”应该用 should/ ought to have done
30、。答案 D。2.、本句的意思是：我胃不舒服，我刚才不应该吃那么多油炸鸡。其实你吃了所以应该选 C。3、本句表达的意思是：你不应该一句话没说就离开家。含有责备的意思，做了不应该做的事情，答案选 B。6. neednt have done 表示“做了本来不必做的事情”，通常不用于肯定句。例如：Its only five minutes walk. We neednt have taken a taxi.只有 5 分钟的步行路程，我们本不必乘出租车的。It is warm today. You neednt have worn your coat.今天天气暖和，你本来不必穿大衣的。巩固练习：1. H
31、e is not poor. You _ have lent him the money.A. cant B. neednt C. couldnt D. mustnt2. There was plenty of time. You _ have hurried.A. wont B. mustnt C. neednt D. couldnt答案简析：1. 该句的意思是：他不穷，你本不必借给他钱。答案选 B.2. 该句的意思是：时间充裕着呢，你不必慌忙。答案选 C。- Catherine, I have cleaned the room for you.- Thanks. you _ it. I c
32、ould manage it myself. A. neednt do B. neednt have done C. mustnt do D. shouldnt have done 7. can/ could have done 表示 “本来能够做而实际上没有做的事情”。例如：You could have come here a little earlier.你本来可以早点来到这儿的。She could have earned a lot of money.她本来可以挣一大笔钱的。巩固练习：He paid for a seat, when he _ have entered free. A.
33、could B. would C. must D. need1. I _ here in time, but I met an old friend of mine. I stopped and talked with him for some time.A. shouldnt have come B. must have comeC. neednt have come D. could have come2. They _ have finished the work yesterday, but it was raining hard.A. must B. could C. should D. might答案简析：1. 这句话的意思是：我本来可以按时来这儿的，但是遇到一位老朋友，说了会话，所以没能及时来这儿。答案选 D。2. 该句的意思是：他们本来可以做天完成工作的，但是昨天雨下的太大，所以没能完成。答案选 B。
