【高中英语语法课件】情态动词和虚拟语气

1、第七讲 情态动词和虚拟语气 0101 0202 情态动词情态动词 1. 情态动词的基本用法|2. 情态动词的推测性用法 3. “情态动词+have done”的用法 虚拟语气虚拟语气 1. 条件句中的虚拟语气 | 2. 宾语从句中的虚拟语 气 | 3. 主语从句中的虚拟语气 | 4. 表语从句和同位 语从句中的虚拟语气 | 5. 其他句型中的虚拟语气 I. 单句语法填空 | II. 单句改错 | III. 翻译句子 | IV. 语法填空 | V. 短文改错 0303 针对训练针对训练 1 PART ONE 情态动词 一、情态动词的基本用法 can/could的用法 (1)表示能力，意为“能，会

2、”。can表示现在，could表示过去。 1 Most people can use WeChat to communicate with others. 大部分人会用微信和别人交流。 No one could work out the challenging question in the exam. 在这次考试中没人能解答出这个具有挑战性的问题。 一、情态动词的基本用法 can/could的用法 (1)表示能力，意为“能，会”。can表示现在，could表示过去。 1 名师指津can表示能力时，有时可以与be able to 换用。但是以下两种情 况只能用be able to 在将来时和完

3、成时中必须用be able to； 表示经过努力而成功地做成某事时，只能用be able to。 I am sure we shall be able to get you a job soon.(不能用can) After years of hard work he was able to win the prize.(不可以用could) 一、情态动词的基本用法 can/could的用法 (2)表示客观或理论上的可能性，意为“可能会”。 1 It can be very warm sometimes in this area. 这个地区有时可能非常暖和。 一、情态动词的基本用法 can/c

4、ould的用法 (3)表示请求或允许。在疑问句中could可以代替can，语气更委婉。 1 Can/Could I have a word with you? It wont take long. 我可以和你谈谈吗？不会花很多时间的。 一、情态动词的基本用法 can/could的用法 (4)can的几个常用句型 1 cant/can never.too /enough 再再也也不过分不过分 You cant praise him too much. 你无论怎样称赞他都不过分。 We can never pay too high a price for the College Entrance

5、Examination. 为了高考，我们无论付出多高的代价也不为过。 一、情态动词的基本用法 can/could的用法 (4)can的几个常用句型 1 “cannot wait to do ”意思是意思是“急于做急于做”，表示强调的肯定意思。，表示强调的肯定意思。 I cannot wait to read the book。 我非常渴望读这本书。 一、情态动词的基本用法 can/could的用法 (4)can的几个常用句型 1 cant/couldnt help doing sth 情不自禁情不自禁地做某事。地做某事。 He couldnt help laughing when he rea

6、d the funny story. 读了这个有趣的故事，他情不自禁地笑了起来。 一、情态动词的基本用法 may/might的用法 (1)表示请求和许可。在疑问句中might可以代替may，语气更加委婉。 2 May/Might I take this book out of the reading room? No，you mustnt. You read it in here. 我可以把书拿出阅览室吗？ 不，绝不可以，你在这儿读。 一、情态动词的基本用法 may/might的用法 (2)表示祝愿，常用结构为“May主语动词原形！” 2 May you be happy every day!

7、 愿你快乐每一天！ 一、情态动词的基本用法 may/might的用法 (3)may的常用句型：“may/might as well动词原形”意为“不妨，最好，倒 不如”。 2 If you think the price of beef is too high，you might as well buy some pork. 如果你认为牛肉太贵的话，你不妨买些猪肉。 一、情态动词的基本用法 must的用法 (1)表示“必须”，语气强烈。 3 Shall I inform him of the change of the schedule right now? I am afraid you m

8、ust，in case he comes late for the meeting. 我该马上通知他日程改了吗？ 我想你必须(通知他)，以免他开会迟到。 一、情态动词的基本用法 must的用法 (1)表示“必须”，语气强烈。 3 名师指津have to “不得不”，强调客观需求，表示因客观原因而不得不 做某事；must 强调主观看法，表示主观上认为必须做某事。试比较： I must learn another language.(主观想法) I have to learn another language.(客观需求) 一、情态动词的基本用法 must的用法 (2)意为“偏要，非要不可”。 3

9、 If you must smoke，please go to the smoking section. 如果你非要抽烟，请到抽烟区。 一、情态动词的基本用法 must的用法 (3)mustnt表示禁止，意为“不得，不允许；一定不要”。 3 You mustnt play with fire; its too dangerous. 你绝对不能玩火，太危险了。 一、情态动词的基本用法 shall的用法 (1)用于第一、三人称疑问句中，表示说话人征求对方的意见。 4 What time shall I pick you up at your house tomorrow，sir? I havent

10、 decided on the time. But I will call you. 先生，我明天什么时候到你家接你呢？ 我还没有决定时间，但是我会给你打电话的。 一、情态动词的基本用法 shall的用法 (2)用于第二、三人称陈述句中，表示说话人的命令、警告、威胁、允诺、决心等； 或用于条约、规定、法令、法律等，意为“必须”。 4 You shall be punished for what you have done. 你必须为你的所作所为受到惩罚。 一、情态动词的基本用法 should/ought to的用法 (1)should表示责任、义务、劝告、建议等，意为“应该”。 5 We sh

11、ould make every effort to protect the wild elephants. 我们应该尽力保护好这些野生大象。 一、情态动词的基本用法 should/ought to的用法 (2)should表示出乎意料的口气，意为“竟然，居然”。 5 Such a gentleman should do that. 这样一位绅士竟然会做那种事。 一、情态动词的基本用法 should/ought to的用法 (3)ought to表示义务或责任，意为“应该”，语气比should稍重。 5 You ought not to be late for such an important

12、 meeting. 这么重要的会议你不应该迟到。 一、情态动词的基本用法 will/would的用法 (1)与各种人称连用，用于陈述句中，表示主语的意志、意愿或决心。will指现在， would指过去。 6 I will never talk to him again. 我再也不愿意和他说话了。 Days later，my brother called to say he was all right，but wouldnt say where he was. 几天后，我的哥哥打电话说他一切都好，但是他不愿说他在哪儿。 一、情态动词的基本用法 will/would的用法 (2)表示征求意见或提出

13、请求，多用于第二人称疑问句中。would比will语气委婉。 6 Will/Would you close the window? 请把窗户关上好吗？ 一、情态动词的基本用法 will/would的用法 (3)表示习惯性动作、固有属性或必然趋势，意为“总是；习惯于”。will指现在， would指过去。 6 Fish will die without water. 没有水，鱼会死的。 When we worked in the same firm several years ago，we would often go to the cinema together. 几年前在同一家公司工作时，我

14、们常常一起去看电影。 一、情态动词的基本用法 need/dare的用法 (1)need既可作情态动词，也可作实义动词；作情态动词时，表示“需要”，常用 于否定句和疑问句中。neednt表示“不必”；对need引出的一般疑问句作肯定回 答时用must而不用need，作否定回答时用neednt。 7 I neednt use a clock to wake me up because at six oclock each morning the train comes by my house. 我不必用闹钟来叫醒自己，因为每天早上六点都有火车从我家房前经过。 一、情态动词的基本用法 need/da

15、re的用法 (2)dare既可作情态动词，也可作实义动词；作情态动词时，表示“敢，胆敢”， 后跟动词原形，常用于疑问句、否定句和条件句中。 7 I am so afraid that I dare not move. 我吓得一动也不敢动。 一、情态动词的基本用法 need/dare的用法 7 名师指津need还可以作实义动词，此时有人称和数的变化，后面可跟名 词、带to的不定式或动名词等作宾语，其否定形式、疑问形式都要通过助动词do构 成。 Do I need to leave my telephone number and address? 我有必要把电话号码和地址留下吗？ You dont

16、 need to hand in your compositions today. 你们今天不必交作文。 二、情态动词的推测性用法 can/ could can用于肯定句中表示客观的可能性，意为“有时会”；用于疑问句中可以表示推 测，意为“可能”，有时表示一种惊讶的语气；用于否定句中也可以表示推测， cant意为“不可能”，语气很强烈。could是can的过去式。 二、情态动词的推测性用法 may/ might may常用于肯定和否定句中；表示某件事情或许会发生，常译为“或许；可能”， might是may的过去式，比may语气更弱。 二、情态动词的推测性用法 must must表示推测时，只能

17、用于肯定句中，意为“一定，必定”，表示十分肯定的语 气(在疑问句中或否定句中要用can/could)。 二、情态动词的推测性用法 should/ ought to should/ought to用来表示推测时意为“应该”，即含有“按道理来说应当如此” 的意思。 He cant have left. His coat is here. 他不可能已经走了。他的外套还在这里。 Mr. Bush is on time for everything. How can it be that he was late for the meeting？ 布什先生做什么事情都很准时，他怎么可能开会迟到呢？ Som

18、eone must have used my umbrella yesterday. I found it wet. 昨天一定有人用了我的雨伞，我发现它湿了。 She promised to come by 10 oclock. She should/ought to be here at any moment. 她答应10点之前来的。她随时都可能来到。 三、“情态动词have done”的用法 must have done表示对过去已发生的事情进行肯定的推断，只用于肯定句中， 意为“一定，必定”，其否定形式为：cant/cannot/couldnt have done。 1 It must

19、have rained last night, for the road was quite wet. 昨晚肯定下雨了，因为路面十分潮湿。 I saw Mr. Wang just now. He couldnt/cant have gone abroad. 刚刚我还看见王先生了，他不可能出国了。 三、“情态动词have done”的用法 could have done意为“本来可以，本来能够”，表示虚拟语气。 2 You could have made greater progress, but you didnt try your best. 你本来可以取得更大的进步，但是你没有努力。 三、

20、“情态动词have done”的用法 may/might have done表示对过去已发生的事情进行推断，意为“可能/或 许已经”。其否定形式为： may/might not have done意为“可能没有 做”。 3 Its no use going to his house. He may not have gone home. He may have gone somewhere else. 去他家没用。 他可能没有回家，可能已经去了别的地方。 三、“情态动词have done”的用法 should/ought to have done表示本应该做某事，却没有做，含有责备或后 悔之意

21、。其否定形式为should not/ought not to have done表示本不该做 某事却做了。 4 With all the work finished, I should have gone to the party last night. 所有的工作都做完了，我昨晚本该去参加宴会的。 You ought not to have made fun of him. He is not the one you laugh at but learn from. 你本不应该取笑他的。他不是你要嘲笑的人而是你应该学习的榜样。 三、“情态动词have done”的用法 neednt have

22、 done表示本没有必要做某事却做了。 5 We neednt have bought so much food now that Suzie wont be with us for dinner. 既然苏西不与我们一起吃晚饭，我们原本不必买那么多食物。 2 PART TWO 虚拟语气 一、条件句中的虚拟语气 虚拟条件句 1 if条件从句条件从句从句的谓语形式从句的谓语形式主句的谓语形式主句的谓语形式 表示现在情况动词过去式(be的过去式用were) should/would/could/might动词 原形 表示过去情况had过去分词 should/would/could/mighthave

23、 过去分词 表示将来情况 should动词原形 should/would/could/might动词 原形 动词过去式 were to动词原形 一、条件句中的虚拟语气 虚拟条件句 1 If I had enough money，I would buy myself a computer first of all.(与现在事实相反与现在事实相反) 如果我有足够的钱，我首先要为自己买一台电脑。 If you had taken my advice，you could have passed the exam.(与过去事实相反与过去事实相反) 如果你按照我的建议去做，你肯定考过了。 If I saw

24、/should see/were to see him tomorrow，I would invite him to my home.(与将来与将来 事实相反事实相反) 如果明天见到他，我会邀请他到我家。 一、条件句中的虚拟语气 错综时间条件句 2 If I were you, I wouldnt have taken his stupid advice. 如果我是你的话，我才不会听他的馊主意。 If you had studied hard earlier, you would be studying at university now. 如果你早点努力学习，你现在就在上大学了。 当虚拟语气

25、中从句的时间和主句的时间指的不是同一个时间时，这时会构成错综时 间虚拟语气，需要根据上下文来判断各自的语气。 一、条件句中的虚拟语气 省略if的倒装句 3 If I were at school again，I would study harder. Were I at school again，I would study harder. 如果我还有上学的机会，我会更加努力地学习。 If they had known what was coming next，they might have had second thoughts. Had they known what was coming

26、next，they might have had second thoughts. 要是他们知道下一步发生什么，他们会三思的。 If it should rain tomorrow，we would not go climbing. Should it rain tomorrow，we would not go climbing. 如果明天下雨的话，我们就不去登山了。 在虚拟条件状语从句中可省略if，把were，had，should提到句首，变为倒装句式。 一、条件句中的虚拟语气 含蓄条件句 4 Without your help, I couldnt have won the prize.

27、要是没有你的帮助，我不可能获得这个奖项。 (1)有时假设的情况并不以条件句表示出来，而是通过一个介词短语或其他方式表示。 常用的有without，but for，under，with等介词。 一、条件句中的虚拟语气 含蓄条件句 4 Your father felt very tired yesterday，or/otherwise he would have taken you to the zoo. 你父亲昨天很累，不然他会带你去动物园的。 She would have helped you，but she was busy yesterday. 她本来能来帮助你的，但昨天她太忙了。 (2)

28、有时虚拟语气可以由otherwise，or，but来引导。 二、宾语从句中的虚拟语气 在建议、愿望、命令等动词后的宾语从句中的虚拟语气 1 下列动词后的宾语从句中的虚拟语气结构为“should动词原形”，should可以 省略。 一主张：insist 二命令：order，command 三建议：suggest，advise，recommend 四要求：request，require，ask，demand 外加一个敦促：urge The school recommends parents (should) not permit their children to swim in rivers.

29、学校建议父母别让他们的孩子在河里游泳。 二、宾语从句中的虚拟语气 在wish后的宾语从句中的虚拟语气 2 (1)对现在情况的虚拟：wish主语动词过去式(be用were) (2)对过去情况的虚拟：wish主语had过去分词 (3)对将来情况的虚拟：wish主语would/could/might动词原形 I wish (that) I were a bird and could fly freely in the sky. 我希望我是一只小鸟，能在天空自由飞翔。 I wish you had come to my birthday party. 但愿你当时来参加我的生日晚会了。 We wish

30、we would fly to the Mars one day. 但愿我们有一天能飞到火星上。 二、宾语从句中的虚拟语气 would rather后的宾语从句中，表示愿望，意为“宁愿；但愿”。用一般过去 时表示与现在或将来事实相反；用过去完成时表示与过去事实相反。3 When my father is upset，he would rather we left him alone. 当我的父亲烦恼的时候， 他更喜欢我们不打扰他。 Id rather you hadnt told me about it. 我宁愿你没有告诉我那件事。 三、主语从句中的虚拟语气 在It is desired/ s

31、uggested/ recommended/ proposed/ necessary/ important/ strange/ natural/ essential/ a pity.that从句中，从句的谓语动词 用“should动词原形”，should可以省略。 It is proposed that a new nature preserve (should) be set up in this area. 人们建议在这个地区建立一个新的自然保护区。 四、表语从句和同位语从句中的虚拟语气 在suggestion，proposal，order，request，advice等名词后的表语从句和

32、同位 语从句中要用虚拟语气，其构成是“should动词原形”，should可以省略。 My advice is that we (should) take the price into account. 我的建议是我们应该把价格因素考虑在内。 Your suggestion that the door (should) be shut when we leave is reasonable. 你的那个当我们离开的时候应该关上门的建议是合理的。 五、其他句型中的虚拟语气 在“It is (about/high) timethat从句”中，谓语动词常用过去式或 “should动词原形”表示虚拟语气

33、，should一般不省略。1 Its high time that we devoted/should devote ourselves to environmental protection. 是我们致力于环境保护的时候了。 五、其他句型中的虚拟语气 as if，as though引导的表语从句和方式状语从句中常用虚拟语气，与现在事 实相反用一般过去时；与过去事实相反用过去完成时。2 It seems as though it were spring already. 看起来好像已经是春天了。(事实上不是) He talked as if he had been to Italy himse

34、lf. 他谈论起来好像自己去过意大利似的。(事实上并没去过) 五、其他句型中的虚拟语气 if only引导的感叹句中，用虚拟语气表示愿望。 2 Look at the trouble were in. If only we had taken our teachers advice！ 看看我们所处的困境，要是我们接受老师的建议就好了！ 针对训练 . 单句语法填空 1Samuel, the tallest boy in our class， _ easily reach the books on the top shelf.(2017北京卷) 2If the new safety system

35、(put) to use, the accident would never have happened. (2017北京卷) 3 _ (be) it not for the support of the teachers, the student could not overcome her difficulty.(2017江苏卷) 4Please remind your grandpa to take medicine on time，for a man of his age _ be very forgetful. 5What do you mean，there are only ten

36、 tickets？There be twelve. can had been put Were can should . 单句语法填空 6Its high time that he _ (do) something instead of just talking. 7We havent seen my aunt for many years. We couldnt wait _ (see)her. 8If you had told me in advance，I _ (meet) him at the airport. 9My father suggests that I _ (take) e

37、nough sleep before the final examination. 10He is so happy. He _ (win)the match. did/should do to see would have met (should) take must have won . 单句语法填空 11When she was a little girl，she _ sit by the window every evening，deep in thought. 12According to the factory safety rules，all accidents _ be rep

38、orted to the safety officer. 13She _ (steal)the dictionary，but Im not sure. 14Look! There are so many mistakes in your composition. You _ (fix)full attention on it. 15We _ (call )a taxi yesterday if Harold hadnt offered us a ride home. would shall may/might have stolen should have fixed would have c

39、alled . 单句语法填空 16If it _ (be) Sunday tomorrow，I should go to see my grandmother. 17We lost our way in that small village，otherwise we _ (visit) more places of interest yesterday. 18He stood up and offered her his seat，as if he _ (read)her mind. 19If we _ (book)a table earlier，we wouldnt be standing

40、here in a queue. 20It is suggested that the meeting _ (put)off till next week. were would have visited had read had booked (should) be put . 单句改错 1. As a kid，I loved to watch cartoons，but no matter how many times I asked to watch them，my parents would not to let me.(2018全国卷) 2We can chose between st

41、aying at home and taking a trip. (全国卷) 3Some classmates suggest we can go to places of interest nearby. (全国卷) 4Sorry，I am too busy now. If I have time，I would certainly go for an outing with you. 5Meanwhile，I found out that with more patience I must make my toys last. choose should或去掉或去掉can had coul

42、d/might . 单句改错 6The order came that the medical supplies should sent to the earthquake-stricken area soon. 7On Sundays when I was a child，father and I will get up early and go fishing. 8If you listened to the doctor，you would be all right now. 9But for the rain，we should have a pleasant journey yest

43、erday. 10My suggestion is that we will hold a meeting this evening. would be had had should或去掉或去掉will . 翻译句子 1你开车时越细心越好。 2他已经长大了，因此，我们不必担心他。 3我不会游泳，但是我相信通过多练习我就能游泳了。 4门口不可能是邮递员，才六点钟。 You cannot be too careful while driving your car. He has grown up，so we dont need to worry about him. I cant swim，but

44、 I am sure I will be able to swim through more exercise. It cant be the postman at the door. Its only six oclock. . 翻译句子 5你本来能做得更好些，但你当时太粗心了。 6没有你的帮助，我无论如何也不会成功。 7我们都同意他让我们去大连旅游的建议。 8同一件事不必对你说两遍。 You could have done better，but you were too careless. Without your help，I wouldnt have succeeded anyway.

45、 /If you hadnt helped me，I wouldnt have succeeded anyway. We all agreed to his suggestion that we (should) go to Dalian for sightseeing. You neednt be told twice about one single thing. . 语法填空 (2019江西上饶六校第一次联考) Beautiful Jiangxi，Showing Her Charm to the World Have you ever imagined how beautiful Jiangxi is? She has 166，900 square kilometers of land，of which 63.1% 1. (cover) by forests. She has five national nature reserves，46 national forest parks，four World Heritage Sites and four World Geological Parks，and nurtures every precious 2. (species)