Unit 5 The Value of Money Discovering Useful Structures （ppt课件）-2024新人教版（2019）《高中英语》必修第三册.pptx

1、can couldmay mightmustshall shouldought to will wouldcan 和和 could 1.表示表示“能力能力”。could表示过去具备的能力。表示过去具备的能力。be able to 表示具体情况下具有的能力，并且做了某动作。表示具体情况下具有的能力，并且做了某动作。be able to 除有一般现在时、一般过去时、一般将来时外，除有一般现在时、一般过去时、一般将来时外，还可有现在完成时、不定式、动词还可有现在完成时、不定式、动词-ing 形式等。形式等。She can drive，but she cant ride a bicycle.I cou

2、ld swim all the way across the lake，but I cant now.This is the information Ive been able to get so far.can 和和 could 2）cant 表猜测。只用于表猜测。只用于否定句，疑问句和感叹句否定句，疑问句和感叹句。cant表示表示“一定不一定不”。现在的状态现在的状态 cant do/be 现在正进行的动作现在正进行的动作 cant be doing过去的动作或状态过去的动作或状态cant have donecan 和和 could 3)用于表示用于表示“许可许可”、“请求请求”。(请求时

3、请求时,用用 could 比比 can 更婉转更婉转,回答用回答用can)1)Can I go with you?(请求请求)我能跟你一起走吗？我能跟你一起走吗？2)Father said I could go to cinema.(表示过去的许可表示过去的许可)爸爸说我可以去看电影。爸爸说我可以去看电影。3)Could I ask you something?我可以问你一件事吗？我可以问你一件事吗？You could have passed the interview.你本来可你本来可以通过面试的。以通过面试的。（实际上没能）（实际上没能）You could at least have se

4、nt five cards.你至少你至少可以寄可以寄5张明信片的。张明信片的。（实际上没能）（实际上没能）I could have run 100 metres in 12 seconds.我本来能用我本来能用12秒钟完秒钟完100米的米的.（实际上没能）（实际上没能）4）could have done指指本来能做而实际未做本来能做而实际未做，表达遗憾的感情色彩。一般没有否定形式。表达遗憾的感情色彩。一般没有否定形式。may might1)表示表示“请求请求”，“许可许可”。may 用于正式场合。用于正式场合。might表示委婉客气，不表示时态。表示委婉客气，不表示时态。Students ma

5、y take 3 books each.Might I ask whether you are using the typewriter?注意：注意：May/might I smoke here?-Yes,you may.Yes,please./Certainly.-No,you mustnt./Please dont./Youd better not.may,might2）表示推测）表示推测“可能性可能性”时，意思是时，意思是“可能可能”、“也也许许”。一般用于肯定句或否定句，一般用于肯定句或否定句，might不表示过去时不表示过去时态，只是表示的可能性更小。态，只是表示的可能性更小。现在的

6、状态现在的状态 may/might do/be 现在正在进行的动作现在正在进行的动作 may/might be doing过去的动作或状态过去的动作或状态 may/might have doneHe may/might be sleeping now.These students may/might have seen the film before.（过去）（过去）注意：注意：may,might表推测时，可用于否定句，意思是表推测时，可用于否定句，意思是“可能不、也许不可能不、也许不”，但，但不用于疑问句不用于疑问句。The boy may/might not be watching TV

7、at home.这个男孩可能没在家看电视这个男孩可能没在家看电视He may/might be American.他可能是个美国人。他可能是个美国人。3）might have done 表示表示“(过去过去)本来可能做某事，本来可能做某事，但实际上没有做到但实际上没有做到”。He might have given you more help，even though he was very busy.即使再忙，他也可能再多给你一些帮助的。即使再忙，他也可能再多给你一些帮助的。1.Tom comes from Australia;hespeak English very well.2.I hear

8、d you bought a new book.I have a look?3.It _be his mother,for she has been ill at home for a long time.4.I dont really like James.Why did you invite him?Dont worry.He _ not come.He said he wasnt certain what his plans were.5.My wallet was gone.I _ have left it on the G9 bus.can May cant mightcouldEx

9、ercisemust(1)表义务、必要性、命令等，表示表义务、必要性、命令等，表示“必须必须”，强调主观看，强调主观看法。法。否定回答时用否定回答时用neednt，表示，表示“不必不必”。“Must I wash the dishes at once？”“No，you neednt.”“我得立刻洗这些盘子吗？我得立刻洗这些盘子吗？”“”“不，不必。不，不必。”【注】【注】mustnt表表“禁止、不准禁止、不准”。You mustnt play with the knife；you may hurt yourself.你不可玩刀子，你会把自己割伤的。你不可玩刀子，你会把自己割伤的。现在的状态现在

10、的状态 must do/be 现在所进行的动作现在所进行的动作 must be doing过去发生过的动作或状态过去发生过的动作或状态 must have done must(2)表表猜测猜测。只表示肯定的猜测。译为。只表示肯定的猜测。译为“一定一定”。2）He must be doing his exercises.他一定在做练习。他一定在做练习。1）I think he must be all right now.我想他现在一定好了。我想他现在一定好了。3）He must have finished the work.他一定已完成了工作。他一定已完成了工作。注注：must表示推测时表示推测

11、时很少用于将来的情况很少用于将来的情况。一般不用一般不用He must come tomorrow.可用可用Its certain/Im sure that he will come tomorrow.（3）在反意疑问句中，当附属部分含有表示推测意义的）在反意疑问句中，当附属部分含有表示推测意义的must时，疑问部分的时，疑问部分的助动词应与助动词应与must后面的动词后面的动词在非推测情况下在非推测情况下的用法的用法保持一致保持一致。He must be a worker,isnt he?他准时个工人，是吗？他准时个工人，是吗？You must have learned English fo

12、r many years,havent you?（现在完成时）（现在完成时）你一定学了好多年英语，是吗？你一定学了好多年英语，是吗？比较：比较：It must have rained last night,didnt it?（过去）（过去）He must have arrived by yesterday morning,hadnt he?（过去完成）（过去完成）shall(1)用于疑问句中，与第用于疑问句中，与第一、三一、三人称连用，表示人称连用，表示征求对方的征求对方的意见意见Shall she go to the concert with us?Shall we go out for a

13、 walk?(2)用于第二、三用于第二、三人称，表示说话人的人称，表示说话人的命令、警告、强制、命令、警告、强制、允诺、威胁或决心允诺、威胁或决心等等Dont worry.You shall get the answer this very afternoon.不要焦急，今天下午你就会得到答复。不要焦急，今天下午你就会得到答复。(允诺允诺)He shall be sorry one day.I tell you.我告诉你，他早晚有一天会后悔的。我告诉你，他早晚有一天会后悔的。(警告警告)should,ought to1)表示表示责备和劝告责备和劝告，意为，意为“应该应该”，后者的语气重些。，后

14、者的语气重些。We should attend the meeting.我们应该参加这次会议。我们应该参加这次会议。(2)可表可表猜测猜测。(有很大的可能性。有很大的可能性。)现在的状态现在的状态should/ought to do/be现在进行的动作现在进行的动作should/ought to be doing过去发生过的动作或状态过去发生过的动作或状态 should/ought to have doneshould(3)(表惊讶、遗憾表惊讶、遗憾)竟然；居然竟然；居然Im glad that your story should have won the first prize.我很高兴你的

15、小说居然赢得头奖。我很高兴你的小说居然赢得头奖。(4)(与疑问词连用，表示意外、纳闷、惊讶等与疑问词连用，表示意外、纳闷、惊讶等)究竟是；究竟是；到底到底Who should come in but my old friend Betty！我当是谁进来了，原来是我的老朋友贝蒂呀！我当是谁进来了，原来是我的老朋友贝蒂呀！1.We should have studied last night,but we went to the concert instead.我们昨晚本应学习的，但我们却去看音乐会了。（实我们昨晚本应学习的，但我们却去看音乐会了。（实际上没有学习）际上没有学习）2.We ough

16、t to have invited everyone.我们应该邀请每一个人的。我们应该邀请每一个人的。should/ought to have done，“本应该本应该”。过去应该。过去应该做而实际并未做的动作。做而实际并未做的动作。(2)shouldnt/ought not to have done，“本不应该本不应该”。过去不应该做而实际做了的动作。过去不应该做而实际做了的动作。我只告诉了你。你不应该告诉其他人的。我只告诉了你。你不应该告诉其他人的。I only told you.You shouldnt have told other people.will，would 1)表示某种表示

17、某种“意愿意愿,意志，决心意志，决心”,would 则更客气。则更客气。2.Will you accept this invitation?你愿意接受这邀请吗？你愿意接受这邀请吗？1.I will call you as soon as possible.我会尽快打电话给你。我会尽快打电话给你。3.She will do it if you ask her.如果你问她，她会做的。如果你问她，她会做的。will,would 2)表示表示请求请求(用用 would 比比 will 表示更客气表示更客气)1.Will you kindly tell me the way to the post of

18、fice?请问到邮局怎么走？请问到邮局怎么走？2.Would you give me your address?请你告诉我你的地址，好吗？请你告诉我你的地址，好吗？will,would 3)will 和和 would 表示表示习惯性习惯性2.He would come to see me when he was in London.(would 表示习惯地表示习惯地)他在伦敦时，常来看望我。他在伦敦时，常来看望我。1.He will sit there hour after hour looking at the river.(will 表示经常地表示经常地)他经常一连几个小时坐在那儿看着河水

19、。他经常一连几个小时坐在那儿看着河水。would：“总是，总要总是，总要”，过去反复发生的动作或某种倾向过去反复发生的动作或某种倾向。强调动作强调动作used to：“过去常常过去常常”，现在已没有这种习惯现在已没有这种习惯。强调动作或。强调动作或状态状态 used to 可与状态动词连用可与状态动词连用,would不可以不可以e.g.He used to be a quiet boy.()He would be a quiet boy.()would used towill,would 其他用法其他用法(4)(表示说话者的厌烦、焦躁表示说话者的厌烦、焦躁)老是；偏要老是；偏要Thats ex

20、actly like Susie.She will/would come to me just when I am/was busy.苏西就是那个样子，她老是在我忙碌的时候来找我。苏西就是那个样子，她老是在我忙碌的时候来找我。(5)(用于否定句中，主语一般是事物，表示某事物暂时用于否定句中，主语一般是事物，表示某事物暂时的特性的特性)就是就是(不能不能)That window wouldnt/wont open.那扇窗户打不开。那扇窗户打不开。可兼做行为动词的情态动词：可兼做行为动词的情态动词：needDo you need any help?You neednt finish that wo

21、rk today.I need hardly tell you that the work is dangerous.neednt have done“本来不需要本来不需要”，表示，表示过去本来没有必要做某事，但事实上却做了。过去本来没有必要做某事，但事实上却做了。I neednt have got up so early;but my neighbors woke me up.我本来不必那么早起来的。可是隔壁邻居把我吵醒了。我本来不必那么早起来的。可是隔壁邻居把我吵醒了。There was plenty of time.She neednt have hurried.当时时间很充足，她本没有

22、必要那么匆忙的。当时时间很充足，她本没有必要那么匆忙的。can 和和 could 1.“能力能力”。2.“许可许可”、“请求请求”3.猜测猜测（否定句和疑问句）（否定句和疑问句）4.本来能做本来能做(could)虚拟虚拟may might1.“请求请求”，“许可许可”2.猜测猜测must1.必须必须2.猜测猜测(肯定猜测肯定猜测)3.禁止禁止（mustnt）4.反意疑问句反意疑问句shall1.征求对方的意见征求对方的意见(第一、三人称）第一、三人称）2.说话人的命令、警告、强制、允说话人的命令、警告、强制、允诺、威胁或决心诺、威胁或决心(第二、三人称第二、三人称）reviewshould,o

23、ught to1.义务，劝告义务，劝告2.推测推测 3.本应该；本不应该（虚拟）本应该；本不应该（虚拟）will,would1.意愿意愿2.习惯习惯neednt1.不必不必2.本来不需要（虚拟）本来不需要（虚拟）reviewwould have done 本来过去会做某事却没有做could have done 表示本来过去能够做而实际未做。should/ought to have done 表示本来过去应该做而实际未做。shouldnt/oughtnt to have done 表示过去不应该做而实际上做了neednt have done 表示本不必要做某事而实际做了must have don

24、e 表示对过去情况进行肯定的猜测,意为“一定已经”may/might have done表示对过去发生的行为的可能性猜测。cant have done表示对过去发生某事的否定猜测,意为“肯定不,绝不可能”。虚拟虚拟推测推测过去将来时过去将来时(The Past Future Tense)过去将来时表示在过去某一时间将要发生的动作或存在的状过去将来时表示在过去某一时间将要发生的动作或存在的状态。态。过去将来时常用在主句谓语动词为过去时态的宾语从句中。过去将来时常用在主句谓语动词为过去时态的宾语从句中。过去将来时句子中有时包含时间状语过去将来时句子中有时包含时间状语 the next day、so

25、on等。等。过去将来时的基本结构是过去将来时的基本结构是“woud+动词原形动词原形”,否否定式是在定式是在woud后面加后面加not。如。如:Jeff knew he would be tired the next day.杰夫知道他第二天会很累。杰夫知道他第二天会很累。He promised that he would not open the letter until 2 oclock.他许诺两点钟之前不会打开信。他许诺两点钟之前不会打开信。除了上述结构除了上述结构,be going to、be about to等结构也用等结构也用在过去将来时中在过去将来时中,如如:They were

26、going to find someone to take part in their bet when they saw Henry walking on the street outside.他们正准备找一个人来参与他们的赌局他们正准备找一个人来参与他们的赌局,这时这时,他们看他们看到亨利走在外面的大街上。到亨利走在外面的大街上。Mrs Thomson was about to sit down to watch the opera when her phone rang.汤姆森夫人刚要坐下看剧的时候汤姆森夫人刚要坐下看剧的时候,她的电话响了。她的电话响了。1.be going to表示事

27、先经过考虑或事先做好安排，而表示事先经过考虑或事先做好安排，而will则表示没有经过事先考虑，只是在说话时做出的则表示没有经过事先考虑，只是在说话时做出的决定。决定。如：如：What are you going to do when you grow up?Theres someone at the door.Ill go and open it.2.will可用来表示事物的倾向性或规律性，可用来表示事物的倾向性或规律性，而而be going to则没有这种用法。如：则没有这种用法。如：People wont live without water.be going to 和和 will3.表示

28、将来意义的表示将来意义的will不可用在条件状语从句中，但不可用在条件状语从句中，但可以用在带条件状语从句的主句中。可以用在带条件状语从句的主句中。will表示表示“意意愿愿”时可以用在条件句中。时可以用在条件句中。如：如：If you are going to join us,we will wait for you.If you will give me a hand,Ill tell you what happened.(第一个第一个will在此表意愿在此表意愿)4.强调从目前的证据或迹象推测可能发生某事时，强调从目前的证据或迹象推测可能发生某事时，常用常用be going to。如：如

29、：What bad weather!It is going to rain.导学稿答案导学稿答案(A)情态动词情态动词1.Tom comes from Australia;hespeak English very well.2.I heard you bought a new book.I have a look?3.If youpass the driving test,youget a new car.4.It is sunny today;wetake an umbrella.5.you like to have dinner with me?6.Jack set out at seve

30、n in the morning;hebe here now.7.When you cross the street,yoube careful with the passing cars.8.Itbe his mother,for she has been ill at home for a long time.9.Icome to the party with you,but I am not sure.10.When he was young,he_climb the small hill every morning.can May can shall should Would must

31、 must cant may would(B)过去将来时过去将来时1.He promised he attend the meeting on time.2.I wasnt sure whether he come the next day so I gave him a call.3.She was fifty-eight then.In two years,she be sixty.4.He said that he(leave)at six the next day.5.He said that he was going(live)in the country when he retir

32、ed.6.He hoped his wife(come)soon.7.He was about _(leave)when someone knocked at the door of his office.8.It was reported that another bridge was(build)across the river the next year.9.He told us that he was going(attend)an important meeting the next day.10.He was to have lunch when the bell rang.wou

33、ld would would was leaving to leave was coming to leave to be builtto attendabout（）1.-Where is Emma?-I cant say for sure where she is,but she_ be out shopping.A.canB.should C.must D.may（）2.Theres no light on they_ be at home.A.cant B.mustnt C.neednt D.shouldnt（）3.The room is so dirty _ we clean it？O

34、f course AWill BShall CWould DDo（）4.You _be tired,youve only been working for ten minutes.A.must not B.wont C.cant D.may not DABC（）5.Peter _ come with us tonight,but he isnt very sure yet.A.must B.can C.may D.will（）6.Michael _ be a policeman,for hes much too short.A.neednt B.cant C.shouldnt D.wont（）

35、7.I thought you _ be hungry,so I have brought you some cakes.A.may B.might C.can D.couldCBB（）8.Come on!We _ hurry because there isnt much time left.A.may B.must C.can D.need（）9.Its nearly seven oclock.Jack _ be here at any moment.A.must B.need C.should D.can（）10.You_ all those clothes!We have a wash

36、ing machine to do that sort of thing A.neednt have washed B.shouldnt have washed C.must not have washed D.can not have washedBCA（）11.Johns score on the test is the highest in the class;he_ last night.A.should study B.should have studied C.must have studied D.must have to study（）12.The room is in a t

37、errible mess;it _cleaned.A.cant have been B.shouldnt have been C.mustnt have been D.wouldnt have been（）13.Nobody knows how people first came to these islands.They _from South America on rafts.A.must have sailed B.can sail C.might have sailed D.should have sailedCAC（）14.Mary was not in her bedroom yesterday afternoon.She _ in her classroom.A.should have been B.must have been C.must be D.should be（）15.Bob said he was going to join our club but he didnt.He _ his mind.A.cant have changed B.wouldnt have changed C.must have changed D.shouldnt have changedBCTHANK YOU