高考英语二轮专项复习：情态动词.ppt

1、I 情 态 动 词 的 定 义情态动词是一种本身有一定的词义，表示说话人的情绪、态度或语气的动词，但不能单独作谓语，只能和其他动词原形构成谓语。Shall we begin now?我们现在就开始吗？You must obey the school rules.你必须遵守校规。情态动词数量不多，但用途广泛，主要有：can(could),may(might),must,need,ought to,dare(dared),shall(should),will(would).II 情 态 动 词 的 位 置情态动词在句中放在谓语动词之前，谓语动词前若有助动词，则在助动词之前，疑问句中，情态动词放在主

2、语之前。I can see you.Come here.我能看见你，过来吧。He must have been away.他一定走了。What can I do for you?你要什么？How dare you treat us like that!你怎么敢那样对待我们!情态动词无人称和数的变化，情态动词后面跟的动词需用原形，否定式构成是在情态动词后面加“not”。个别情态动词有现在式和过去式两种形式，过去式可以用来表达更加客气、委婉的语气，时态性不强，可用于过去，现在或将来。He could be here soon.他很快就来。We cant carry the heavy box.我们

3、搬不动那箱子。Im sorry I cant help you.对不起，我帮不上你。情 态 动 词 的 特 点 情 态 动 词 的 用 法A.can 和 could （could 为 can 的过去式）1.表示“能力”、“许可”、“可能性”等。在口语中，can可以代替may表示许可，而may比较正式。What can you do?You can go now.At that time I thought the story could not be true.（能力）（许可）（可能）2.could可以代替can，表示语气较为婉转。Could you help me,please?请问,你能帮

4、助我吗?3.can 和 be able to 都可以表示能力，意思上没有区别，但can 只有现在式和过去式(could)，而be able to 则有更多的形式。No one is able to do it.We shall be able to finish the work next week.I havent been able to finish the bookNo one can do it.could was/were able to的区别：could 只表有能力，was/were able to 意含”经过努力”、“凭借才能”,还可以表示结果They worked hard,

5、so they were able to do more for the company.He could cure the old mans illness.He was able to cure the old mans illness.(能治好)(治好了)B.may 和 might (might是 may的过去式)1.表示允许或征询对方许可，有“可以”的意思。用作此意时，它的否定形式可用may not，但是在表示“不可以”、“禁止”、“阻止”等意思时，常用must not(mustntt)代替may not。You may take the book home.He said that

6、I might borrow this book.-May I watch TV after supper?-Yes,you may.-No,you mustnt./No,you may not./No,youd better not.在请求对方许可时，可用Might I 代替May I?表示更礼貌一些。Might I use your telephone?2.表示可能性，有“或许”、“可能”的意思。might语气更不肯定。He may be right.I hear there may be a few copies left.He may come today(tomorrow).He m

7、ight come today(tomorrow).C.must，have to 和 ought to1.must 表示“必须”。否定式must not(mustnt)表示“不应该”、“不许可”、“不准”、“禁止”等。Everybody must obey the rules.The work must be finished as soon as possible.You mustnt lend it to others.You mustnt speak like that to your mother.在回答有“must”的询问时，否定式常用need not(neednt)/dont ha

8、ve to表示“不必”,而不用must not,因为must not 表示“不可以”-Must I go now?-Yes,you must.-No,you neednt.No,you dont have to.2.must 表示推测（“一定”、“必定”），只用在肯定句中 You must be hungry after the long walk.The Chinese language must have the large number of speakers.must+have+done，表示现在对过去事物的推测。He must have told my parents about i

9、t.他一定把这件事情告诉我父母亲了。3.must 和 have to 的区别:must 表示说话人的主观看法,have to “不得不,必须”，表示客观需要、客观条件只能如此。have to 比 must 有更多形式。I dont like the TV set.I must buy a new one.The TV set is broken.I have to buy a new one.He had to spend his childhood in hard work,helping his father on their small farm.（主观看法）（客观需要）4.ought

10、to可表示义务，要求或劝告，常译作“应该”、“应当”等(和should差不多，只是预期稍重一些)，有时表示非常可能的事情。You should follow your fathers advice.-Ought he to go?-Yes,he ought to.If she is completely well,she ought to be back at school today.ought to+have done指过去动作,表示一件事情该做而未做。ought not to+have done表示一件不该做的事情却做了。D.need 和 dare1.need 表示“需要”、“必须”。通

11、常用在否定句或疑问句中。He neednt pay for it.-Need you go now?-Yes,I must.-No,I neednt.2.dare 表示“敢”。通常用于否定句、疑问句和条件从句中。How dare you say Im unfair?She dare not do so.need 和 dare 也可用作行为动词，变化与一般动词相同“neednt+have done”表示过去做了没必要做的事情。You neednt have taken it seriously.这件事情你不必太认真。She didnt need to go.-Who dares to go?-I

12、 dont dare(to)go.I dare say 作插入语,我想,大概,可能,或许E.shall 和 should1.shall 作为情态动词，用于第二、第三人称，表示说话人的意愿，有“命令”、“警告”、“威胁”、“强制”、“允诺”等意思。You shall do as I say.Tell him that he shall have the book tomorrow.（命令）（允诺）2.在疑问句中，shall 用来征询对方意见或请示指示，用于第一、第三人称。Where shall I wait for you?Shall he come at once?Shall we start

13、 the meeting now?3.should 作为情态动词，表示“劝告”、“建议”时，可译作“应该”。You should keep your promise.Young people should learn new things.should+have done 指过去动作,表示一件事情该做而未做。should not+have done 表示一件不该做的事情却做了。-Who did it sound like?Anybody you know?-Well,perhaps Jeff.I should have asked who was calling before he hung

14、it up.F.will 和 would 1.will(1)will 表示“意志”、“意愿”，可用于多种人称。I will tell you all about it.He wont go.(2)will 在疑问句中用语第二人称时，表示询问对方的意愿或向对方提出请求。Im going to go shopping after school.Will you go with me?Will you please give him a message when you see him?(3)表示习惯动作，有“总是”、“惯于”的意思。Hell talk for hours if you give h

15、im the chance.2.would(1)Would是will的过去式，表示过去时间的“意愿”、“愿望”，用于多种人称。They said that they would help us.I promised that I would do my best.(2)表示说话人的意愿或向对方提出请求，语气比will 婉转。指的是现在时间。Would you like some bananas?Id like to see your new bicycle.-Would you like to see a film?-Yes,Id like to.-Thanks.Im afraid not./

16、Im afraid I wont be able to.(3)表示过去的习惯动作。She would sit like that for hours.Everyday she would get up at six oclock and light the fire.和used to区别：used to常常含有“现在不”之意。此外，would表示“过去常常”时后面动词须是某种行为或动作，不能是静态动词。When young,he would go out for a trip on Sundays.When young,he used to go out for a trip.Near the

17、 village,there _ be a stream.A.would B.used to(Now maybe still does)(But now he doesnt)ORDER:might may could can should mustUNCERTAIN CERTAIN 情态动词表推测must have done,may/might have done 表示猜测can与have done 连用时,为否定句或疑问句,表示猜测neednt have done 表示”本来不必做(却做了)”而neednt do 则表示”不必做(也没做)”ought to/should have done

18、表示”本来应当做的却做”would/could/might/should+have done 用来表示与过去事实相反的虚拟句If I had been free that day,I would have gone with you.情态动词+have done 情态动词专练题1.Put on more clothes.You be feeling cold with only a shirt on.A.can B.could C.must D.would2.Must I drive to his house and pick up the children?No,_.A.you should

19、nt B.you might not C.you neednt D.you mustnt3.You to attend the meeting,but you didnt.A.should come B.would have come C.came D.should have come4.We didnt see Tom at the meeting yesterday.He it.A.mustnt have attended B.cannot have attended C.neednt have attended D.would have not attended5.Tom went on

20、 foot,but he by bus.A.might go B.may go C.could have gone D.ought have gone 6.We play chess than bridge.Some of us dont know how to play bridge.A.had better B.would better C.would rather D.had rather7.There is someone knocking at the door.it be Tom?A.Can B.Must C.Should D.Ought8.There was a lot of t

21、ime.He.A.mustnt have hurried B.neednt have hurried C.could have hurried D.ought to have hurried9.We didnt study Chemistry last night,but we.A.had studied B.could C.should D.could have10.One ought for what one hasnt done.A.not to be punished B.to not be punished C.to not punished D.not be punished 11

22、.May I pick a flower in the garden?.A.No,you neednt B.Not,please C.No,you mustnt D.No,you wont12.Could I call you by your first name?Yes,you.A.will B.could C.may D.might13.Two years ago,my husband bought me a bicycle.If you live in town,it is often faster than a car and you worry about parking.A.mus

23、t not B.may not C.should not D.dont have to14.I didnt see her in the meeting-room this morning.She at the meeting.A.mustnt have spoken B.shouldnt have spoken C.neednt have spoken D.couldnt have spoken15.I wonder how he that to the teacher.A.dare to say B.dare saying C.not dare say D.dared say 16.You

24、 take your umbrella.I am sure it wont rain.A.shouldnt B.cant C.dont have to D.mustnt17.The dog hibernate in winter.A.dont need B.doesnt need to C.needs not to D.needs not18.Look what you have done.You have been careful.A.should B.can C.must D.may19.Tom did not go to the party yesterday,or I him.A.wo

25、uld see B.could meet C.might have seen D.might see20.Lets go to the cinema,shall we?A.No,I cant B.Yes,I will C.Yes,thank you D.No,wed better not 21.If you had been more careful,you have made so many mistakes.A.wont B.wouldnt C.may not D.mustnt22.Whenever Mother was not here,the children make a lot o

26、f noise.A.will B.would C.were to D.were going to23.Why is it so dark.There be a heavy rain coming.A.shall B.may C.should D.will24.Tom is late.What to him?A.should have happened B.must have happened C.can have happened D.would have happened25.Tom,you play with the knife,you hurt yourself.A.wont,could

27、 B.mustnt,may C.shouldnt,must D.cant,should 26.“Can you imagine how about it?”“No,I cant.”A.could they know possibly B.could they possibly know C.they could possibly know D.possibly they could know27.Tom full marks,but he was too careless a spelling mistake.A.could gain,to make B.could have gained,t

28、o make C.could have gained,and made D.could have gained,as to make28.I wonder how she the drunken sailor the other day.A.dare fighting off B.dared fight off C.dare to fight off D.dared fighting off29.the man there be our new teacher?He be,but Im not sure.A.May,mustnt B.Can,may C.Must,cant D.Can,cant30.Someone is knocking at the door.Who it be?It be Tom.He is still in the school.A.can,cant B.can,mustnt C.might,could D.might,may