高一人教新课标必修3unit1情态动词课件.ppt

Grammar,情态动词,生活中的情态动词,Descriptors:describe the pictures by making up sentences including modal verbs.,2.You should listen to the teacher carefully.,1.You had better take an umbrella in case it rains.,4.His bike is broken.He has to walk to school.,3.Can you tell me where the supermarket is?,概述,情态动词表示说话人的某种语气或感情,不能单独作谓语,必须和行为动词或连系动词一起构成谓语。情态动词没有人称和数的变化。(be able to/have to例外）,I can speak English very well.He can speak English very well.He cant be a teacher.,情态动词总汇：,can/could/be able tomay/mightwill/would(used to)shall/should(ought to)must/have toneed/dare,一、can 和could(be able to),表示能力，意为“能，会”,could 为can 的过去式。其否定式为can not/cannot,could not或简写成 cant,couldnt,Tom can swim very well now.Tom couldnt swim very well at the age of 4.,can与be able to的区别：,1）can只有过去式，而be able to有各种时态,2）can表示具备某种能力，而be able to则表示 经过努力成功地做到某事,If he studies hard,he will be able to pass the final exam.,At first he didnt agree with me,but I was able to persuade him.,2.表示请求（可不可以）和许可（可以），表示请求时用can和could都可，could语气更 委婉，而不是can的过去式；表示许可时只能用can,不能用could.,-Can/Could I come in?-Yes,you can.,3.（表示猜测）可能 多用于疑问句和否定句中，can的可能性比 could大，其否定形式是cant/couldnt（不可能）,Can it be true?It cant be true.,用于肯定句中，表示理论上的可能（有时候会）,My sister can be really stubborn.This street can be rather crowded in rush hours.Anybody can make mistakes.,4.特殊句式 can not/can never too或cannotenough“再也不过分，越越好”One cant be too careful.=One cant be careful enough.,cant help doing/cant help but do禁不住，不由得,Hearing the funny story,I couldnt help laughing.,Practice:,2.The World Wide Web is sometimes jokingly called the World Wide Wait because it _ be very slow.,A.Should B.must C.will D.can,D,An Englishman who _not speak Italian is now working in an Italian school.A.must B.can C.may D.might,B,二、may 和might,表示请求或允许（可以）might比may语气更委婉。肯定回答用Yes,you may./Yes,please./Certainly./Sure,go ahead.否定回答用No,you mustnt./No,youd better not.,-May I ask you a question?-Yes,please./Sure,go ahead.,-May I smoke here?-No,you mustnt./No,youd better not.,2.（表示可能性）“可能，也许”只用于陈述句，不用于疑问句，might的可能性比may小。may not表示“可能不”，cant 表示“不可能”,May what he said be true?Can what he said be true?,3.may 用于表示祝愿、希望、乞求等，主要用于正式场合或书面语中。May+主语+动词原形May you succeed!祝你成功!May your dream come true!愿你梦想成真！May God bless you!愿上帝保佑你!,4.may/might as well 动词原形“还是的好”You may/might as well go to see a doctor.5.用于一些状语从句中（目的状语从句“以便，为了”；让步状语从句“即使，尽管，无论”）He got up early in order that he might catch the first bus.Try as he might,Im afraid he could hardly succeed.,三、will 和would,will 和would可表示说话者或主语的意愿，决心，意向 He would never give up.I will do all that I can to help you.2.will用于祈使句的反意疑问句中。Dont forget to close the door,will you?Go with me,will you?,3.will表示现在习惯性的动作；would可表示过去 的习惯动作，此时的意义接近used to The old man will sit by the window for hours.He would sit there doing nothing.,would与used to的区别：,1）used to强调今昔对比（过去这样，现已不是这样）；would只是回顾过去2）would只能表示过去习惯性的动作，而used to 既可表示动作，也可表示状态,4.用于第二人称疑问句中，表示请求、建议或询问对方意愿,would比will语气更委婉 Would/Will you pass me the bottle?Would you like a cup of coffee?5.will可表客观事实、功能或属性。The door wont open.,On Sundays,when I was a child,I used to/would get up early and do morning exercise.There used to be a supermarket near the hospital.,1.在疑问句中，用于第一、第三人称，用来征询对方意见、请求指示或提出建议。,四、shall,What shall we do now?（征求对方意见）Mr.Smith wants to see you,manager.Shall he wait outside or in the office?（请求指示）It is a nice day.Shall we go out for a picnic?（提出建议）,2.用在第二、第三人称陈述句中，表示说话人的“允诺、警告、命令、威胁、决心”等语气。,If you dare do that,you shall be punished.(警告，威胁）If you pass the college entrance examination,you shall get a computer.（允诺）Nothing shall stop us from carrying out this plan.（决心）,3.应该,应当.用于条约，规定，规章等文件中，表示一种义务，多用于第三人称中。,He shall have the right to own the house according to the law.（法律条文）-Can I pay the bill by check?-Sorry,sir.But its the management rules of our hotel that payment shall be made in cash.（规章制度）,4.用在 Lets do sth.的反意疑问句中。,Lets go swimming,shall we?,思考：let us do 的反意疑问句,Practice,It has been announced that candidates(候选人）_ remain in their seats until all the papers have been collected.A.can B.will C.may D.shall,2.-The room is so dirty._ we clean it?-Of course.A.Will B.Shall C.Would D.Do,D,B,五、should,1.表示义务或责任，建议或劝告，意为“应该”,You should keep your promise.Students shouldnt smoke.,2.表示推测“按道理说应该会，想必会”（按照常识或以往的经验）You should be hungry after the long walk.The watch should be ready by 12:00.,3.表示说话人对某事不能理解，可翻译成“居然”，“竟然”，“竟会”，表示意外和出乎意料。,It is surprising that he should have made such a foolish mistake.,I m glad that your story should have won the first prize.,4、表示语气较强的假设（用于条件句中）“万一”,If the car should break down on the way,you would have to walk back.,5.用于表示命令、建议、要求的词后面，可省略。,He suggested that they(should)not waste time playing.,Practice,1.You cant imagine that a well-behaved gentleman _ be so rude to a lady.A.Might B.need C.should D.would,2.I often see lights in that empty house.Do you think I _ report it to the police?A.should B.may C.will D.can,C,A,六、must,1、表示义务或必要性，“必须，应当”,must的否定式是must not/mustnt，意思是“不可以、禁止”，语气强烈。,You must go to bed now.You mustnt play with the knife;you may hurt yourself.,由must引出的一般疑问句，肯定回答用must，否定回答用neednt 或dont have to,Must I stay at home?我必须留在家里吗？Yes,you must.是的，你必须留在家里。No,you neednt.或No,you dont have to.（不，不用了。）,must和have to的区别：,表示（主语）主观的义务或必要时用must；表示（主语）客观因素、客观需要时用have to。have to含有“不得不”的意思。,I havent seen her for ages.I must phone her up.There is no bus here,and I have to go on foot.,2、表示推测“一定，肯定”,No one is answering the phone.They must be out./You must be joking.,3、表示固执、主张、不满等“偏要，硬要，非得”常用于疑问句和条件句中。,-How old are you,madam?-If you must know,I am twice my sons age.John,must you practise playing the piano deep into the night?,must be/must be doing/must have done,Practice,1.-Must we do it now?-No,you_.A.wont B.neednt C.cant D.dont,2.Tom,you _leave all your clothes on the floor like this.A.wouldnt B.mustnt C.neednt D.may not,B,B,七、need 和dare,need 意为“需要”，dare 意为“敢于”作情态动词时，常用于疑问句和否定句中,2.need 和dare 既可作情态动词用，也可做实义动词用,-Need we do it now?-Yes,you must./-No,you neednt.,判断正误:,He darent to speak English before such a crowd,did he?,He darent speak English before such a crowd,dare he?,Nobody need to be afraid of catching the disease.Nobody need be afraid of catching the disease.,3.need 作为实义动词的一种特殊的用法,Thegardenneedswatering/to be watered.Thebabyneedslooking after/tobelooked after.,类似用法的动词：,want require deserve,need doing=need to be done,These dishes need be cleaned carefully.These dishes need to be cleaned carefully.These dishes need cleaning carefully.The poor couple need take care of.,八、情态动词+have done（陈述过去）,must have donemay/might have donecant/couldnt have donecould have doneshould/ought to have doneshouldnt/oughtnt to have doneneednt have done,一定/肯定做过某事也许/可能做过某事不可能做过某事本能够做某事却未做 本应该做某事却未做 本不该做某事却做了 本没必要做某事却做了,John might have gone abroad,but I am still not sure about it.I didnt see her at the party.She couldnt have been there.I could have helped you,but I had an extra task to finish.You shouldnt have told him the truth.You neednt have come so early.,只用can,有时会不可能可能/会吗,也许/可能可能不,理应(不)，想必(不)会,肯定/一定,Practice,1.Helen _go on the trip with us,but she isnt quite sure yet.2.-Do you know where David is?-Well.He _ have gone far-his coats still here.3._ it be true?4.-I have bought 20 pints of beer for our gathering.-That _ be enough.4.He _ have achieved all his aims,but his efforts were worthy of praise.5.The water keeps running from their kitchen.Something _ have gone wrong with their tap.6.It _ be dangerous to practise gymnastics alone.,may,cant/couldnt,Can,may not,must,can,should,请求许可/允许(只能用can),请求许可/允许(只能用may),征询意见、请求指示、提出建议,征询意见、请求指示、提出建议,Practice,1.-_ I use your ruler?-Yes,you_.2._ you tell me how to get the railway station?3.-_ we go for a walk after supper?-Good idea.4._ he wait in the office or outside?5.When _ we start?6.-_you please tell her the news when you see her?,May/Might/Can/Could,can/may,Can/Could,Shall,shall,Will/Would,Shall,