高考英语二轮复习精品课件：专题二语法 第6讲情态动词与虚拟语气(大纲版湖北专用)

1、,语 法,第6讲 情态动词与虚拟语气,情态动词,情态动词主要用来表示说话人的看法、态度等，它是英语动词中最难把握的一类，也是每年高考必考内容。它的语法特征： 1.情态动词不能表示正在发生或已经发生的事情，只表示期待或估计某事的发生。 2.情态动词除ought 和have 外，后面只能接不带to 的不定式。 3.情态动词没有人称和数的变化，即情态动词第三人称单数不加s。 4.情态动词没有非谓语形式，即没有不定式、分词等形式。,1. can表示能力，可能 (过去时用could), 只用于现在式和过去式(could)；be able to可以用于各种时态。 They will be able to

2、tell you the news soon. 2.只用be able to的情况： 位于助动词后 情态动词后 表示过去某时刻动作时 用于句首表示条件 表示成功地做了某事时，只能用was/were able to，不能用could。 He was able to flee Europe before the war broke out.= He managed to flee Europe before the war broke out.,情态动词,注意：could不表示时态 提出委婉的请求（注意在回答中不可用could）。 Could I have the television on? Y

3、es, you can./No, you cant. 在否定句、疑问句中表示推测或怀疑。 He couldnt be a bad man.,情态动词,表示允许或请求；表示没有把握的推测；may 放在句首，表示祝愿。 May God bless you! He might be at home. 注意：might 表示推测时，不表示时态，只是可能性比may 小。 may/might as well后面接不带to 的不定式，意为“不妨”。 If that is the case, we may as well try.,情态动词,1.两词都是“必须”的意思，have to 表示客观的需要，must

4、 表示说话人主观上的看法，即主观上的必要。 My brother was very ill, so I had to call the doctor in the middle of the night.(客观上需要做这件事) He said that they must work hard.（主观上要做这件事） 2.have to有人称、数、时态的变化，而must只有一种形式。但must 可用于间接引语中表示过去的必要或义务。 He had to look after his sister yesterday. 3.在否定结构中，dont have to 表示“不必” ; mustnt表示“

5、禁止”。 You dont have to tell him about it.(不一定要) You mustnt tell him about it.（一定不要）,情态动词,“情态动词+动词原形”表示对现在所发生事情的推测。 “情态动词+have done”表示对过去所发生事情的推测。 1. may (might)表示主观的推测，“也许，可能”，一般用于肯定句，其否定式may not表示“可能不”。 He may not come tonight. He may not have finished the work. 2. can (could)表示主观的推测时，常用于否定句和疑问句；用于肯

6、定句时，表示一时的，客观的可能性。can not表示“不可能”；could have done表示“本可以”。 He cant be at home, since I met him in the street. You could have done better, but you didnt try your best.,情态动词,3. must表示主观的推测“一定”，语气十分肯定，其否定形式为cant，不用mustnt。 He must be in the classroom now. He must have known the truth. 注意：如果要表示对过去情况否定的推测，不能

7、用mustnt，要用cant have done或couldnt have done来表示：“不可能做了某事”。 He cant have been to Beijing, for he knows too little about it. 4. should表示根据常规经验作出的判断，“想必，应该”。 Today is Sunday, our teacher should be at home. You should not have climbed that hill. You might have killed yourself.,情态动词,虚拟语气,语气是以动词形式表现出来的语法特征，

8、 它表示说话人对事物所持的态度。 1.陈述语气：She is very clever. 2.祈使语气：Dont be late for the meeting. 3.虚拟语气：（表示假设的情况、主观愿望等） If there were no gravity, we should not be able to walk.,1.真实条件句用于陈述语气， 假设的情况可能发生， 其中 if 是“如果”的意思。 句型：,虚拟语气,If he comes, he will bring his violin.,2.非真实（虚拟）条件句 时态：可以表示过去、现在和将来的情况。它的基本特点是时态推后。,虚拟语气

9、,If I were you, I would give AIDS patient a hug. If he had been there, it wouldnt have happened. If I had HIV, I would know because I would feel sick.,1. 虚拟语气在宾语从句中的运用,虚拟语气,wish+宾语从句表示不太可能实现的愿望,“要是就好了”。 表示现在不能实现的愿望,从句的谓语动词常用一般过去时态。 表示将来不能实现的愿望, 从句的谓语动词常用“would/could + 动词原形”。 表示过去不能实现的愿望，从句中的谓语动词常用“h

10、ad + 过去分词” 或 “could/should +have +过去分词”。 I wish I were a soldier in the earthquake. I wish the people had known the news earlier. I wish I could fly to Sichuan to help the people there.,1. 虚拟语气在宾语从句中的运用,虚拟语气,表示建议、命令、请求等的动词：suggest, advise, propose, demand, require, insist, request, command, order等后面

11、的宾语从句中，谓语动词需用“should + 动词原形”，其中should 可以省略。 The doctor advised that she (should) be operated.,虚拟语气,2. 虚拟语气在同位语从句和表语从句中的运用 作表示建议、要求、命令等的名词：advice, idea, order, demand, plan, proposal, suggestion, request 等的表语从句或同位语从句中，谓语动词要用“（should）+动词原形”。 His suggestion that we (should) go to Qingdao for holiday is

12、 wonderful.,3. 虚拟语气在主语从句中的运用,虚拟语气,在有些主语从句中，谓语动词用“should + 动词原形”的结构，表示“惊奇，不相信，理应如此”等。 It is necessary (important, natural, strange, etc.) that we should help the people who suffered the major earthquake. It is a shame (a pity, no wonder, etc.) that you should be so careless. It will be desired (sugge

13、sted, decided, ordered, requested, proposed, etc.) that the lost pilots should be searched for in no time.,3. 虚拟语气在主语从句中的运用,虚拟语气,注意：这种从句表示的是事实， 如果说话人对这种事实表现出惊奇等感情色彩则用虚拟语气，否则从句部分用陈述语气。 It is a pity that so many people have been killed in the disaster.,1. 虚拟语气在 as if/as though, even if/even though等引导的

14、表语从句或状语从句中，如果从句表示的动作发生在过去，用过去完成时; 指现在，则用一般过去时;指将来，则用过去将来时。 Even if he had been here, the problem couldnt have been solved.,虚拟语气,2. 虚拟语气用于定语从句中。 这种从句常用于句型 “It is (high ) time (that)”中，定语从句的谓语动词用一般过去时 (be用 were) 或 should(不能省略) +动词原形，意思是“（现在）该”。 Its time that I should make preparations for the party. I

15、ts time that we were going to the exhibition. 3. 虚拟语气在 if only引导的感叹句中的运用。 If only I had known the news earlier, I would not have left.,虚拟语气,4. 虚拟语气在一些简单句中的运用。 情态动词的过去式用于现在时态时，表示说话人谦虚、客气、有礼貌或委婉，常出现在日常会话中。 Would you be kind enough to carry the bookcase for me? 用于一些习惯表达中。 Would you like a cup of tea?,虚

16、拟语气,5.含蓄虚拟条件句 将条件隐含在分词短语中 Falling this time, what would you do? 隐含在介词短语或连词中（without, but, but for, otherwise, or, or else等） But for the government, they wouldnt have rebuilt their homeland in such a short time. =If it were not the government, they wouldnt have rebuilt their homeland in such a short

17、time.,虚拟语气,6.错综虚拟语气两种情况： 从句与过去事实相反，而主句与现在事实相反。 If you had not been strict with me when I was young,I could not be such a successful person now. 主句为祈使句、条件句与将来事实相反，表示说话人认为某件事情发生的可能性很小。 If anyone should come and ask for me, tell them I will come back tomorrow.,虚拟语气,（2009全国卷） I cant leave. She told me t

18、hat I stay here until she comes back. A. can B. must C. will D. may,must 必须。,考点一: 情态动词的基本用法,（2009四川） I dont care what people think. Well, you . A. could B. would C. should D. might,考查情态动词的用法。答话的人提了一个建议你应该关注别人对你的评价。should可以用来向别人提建议，所以答案为C。,（2009四川） You speak very good French! Thanks. I French in Sichuan University for four years. A. studied B. study C. was studying D. had studied,考查时态。我在四川大学学过4年法语是指过去发生的事情，所以谓语动词用一般过去时表示过去的学习（工作）经历。,（2009海南）What do you mean, t