2022新人教版八年级上册《英语》ppt课件：情态动词 (共23张PPT).ppt

1、有一定的词义，但词意不完有一定的词义，但词意不完整整,不能单独作谓语，必须和不能单独作谓语，必须和实义动词连用实义动词连用,表说话人对某表说话人对某一动作或状态的态度和看法。一动作或状态的态度和看法。情态动词后面跟动词原形，情态动词后面跟动词原形，没有人称和数的变化。没有人称和数的变化。情态动词否定式否定式简略形式CanCouldMayMustShallShouldWillwouldCannot/can not CouldMay notMust notShall notShould notWillwouldCantCouldntMayntMustntShantShouldt1)can和和cou

2、ld例 句1)My mother can use the computer now.2)She can swim fast,but I cant.3)Can I play football now,Mum?4)You can use my dictionary.5)Can the news be true?6)He cant have gone there alone.用法can表能力表能力表请求、表请求、允许允许表推测表推测(否、疑否、疑)could1)He could write poems when he was ten.2)She couldnt understand me at th

3、at time 3)Could I ask you a question?表过去表过去能力能力表委婉表委婉请求请求can和和be able to表示能力时用法相同。表示能力时用法相同。can只有现在和过去时，而只有现在和过去时，而be able to则有更多的则有更多的时态形式。表经过努力时态形式。表经过努力,成功地完成某事，通成功地完成某事，通常不用常不用can,而用而用be able to(相当于相当于manage to/succeed in doing sth)。The wounded man _get to the village and was saved in the end.A.

4、could B.was able tocan/could,be able to区区别别2）may与与mightmay 例 句1)May I borrow your typewriter?Yes,you may.No,you mustnt./No,you cant.2)It may rain tomorrow.She may be at home.用法用法表请求表请求许可许可肯定句肯定句表推测表推测might1)He is away from school.He might be sick.表推测表推测可能小可能小3)must/have tomust例句例句用法用法1)You must stay

5、 here until I come back.2)Must I hand in my homework right now?No,you neednt./dont have to.Yes,you must.3)The light is on,so he must be at home now.4)It must have rained last night.表主观表主观看法看法肯定句肯定句表推测表推测have to1)Its too late,I have to leave now.2)You wont have to wait for me.表客观表客观需要需要have to表客观上的需要

6、表客观上的需要,可用于现在时、将来时和过可用于现在时、将来时和过去时。去时。Must表个人意志和主观上的需要，用于现在表个人意志和主观上的需要，用于现在时和将来时时和将来时;表规章制度表规章制度Must为必须为必须,mustnt为禁止为禁止,回答回答must问句问句,肯定用肯定用must,否定用否定用neednt或或dont/doesnt have to表不必表不必;must还表示肯定的推测。还表示肯定的推测。用用Must,have to填空填空1.I know I _ study hard.2.My mother is ill.I _ look after her at home.Must,

7、have to区别区别 musthave tocan,may/might,must表推测表推测Can用于否定句和疑问句用于否定句和疑问句,相当于相当于be impossible;may/might 相当于相当于be not certain,用于肯定句用于肯定句,might可能性低于可能性低于may;must相当于相当于be certain,表有把握的揣测表有把握的揣测。用用can,may/might,must填空填空1.Please ask that man.He _ know that.2.The light is on,so he _ be at home.3.It _ be Wei Fa

8、ng.She is at school now.4.Are you coming to Jeffs party?Im not sure.I_go to the concert instead.maymustcantmight4)need1)Need作情态动词时作情态动词时,表表“必要必要”,多用于否定句或多用于否定句或疑问句疑问句,一般不用于肯定句。回答一般不用于肯定句。回答need问句问句,肯定肯定用用must,否定用否定用neednt。No,you neednt.Need I stay here any longer?Yes,you must.We neednt hurry.2)need作

9、实义动词作实义动词,有人称、数和时态变化有人称、数和时态变化,后多接后多接动词不定式。动词不定式。He needs a new coat.用用Need的适当形式填空。的适当形式填空。1)He _ money now.2)_ she _ to bring the book here?3)We _ work that day.(not)4)The boy _ any help.(not)needsDoesneedneednt/didnt need todoesnt need5)shall和和shouldShall例例 句句1)Shall we go out for a walk?2)What sh

10、all we drink?用法用法征求对征求对方意见方意见should1)We should protect our environment.2)You should do it better next time.劝告建议劝告建议义务责任义务责任用用shallshould填空。填空。1.When_we meet?2.You_see a doctor.shallshould6)will/wouldwill1)I will help you if I am free this afternoon.例句例句用法用法意愿意意愿意志打算志打算would1)I told him that I would

11、go along with him.2)Would you please not smoke here?3)When I was a child,I would go swim-Ming with other children in summer.4)I would have two wings and then fly to the moon.主观愿意主观愿意征求意见征求意见过去习惯过去习惯未来想象未来想象Would you like to do sth?Yes,Id like/love to.Sorry,I have to do sth.I cant.Would you like sth?

12、Yes,please./All right./Ok.No,thanks.Would句型巧回答句型巧回答日常生活中常用日常生活中常用would问句问句,向对方礼貌地提出建向对方礼貌地提出建议或邀请议或邀请,我们尤其要注意口语交际中它的回答。我们尤其要注意口语交际中它的回答。7)had better1)We had better go now.2)You had better not give the book to him.had better建议建议(最好最好做某事做某事)When you are sleeping,you had better_ All your windows closed

13、.(江苏南通江苏南通)A.dont keep B.not keepC.Not to keep D.not keeping注意注意:had better有强硬命令的语气有强硬命令的语气,对长辈不宜使用对长辈不宜使用It must be a ball.BALLIt may/might be a basketballball.Whats this?1）在一定场合下熟练运用不同的情态动词。2）识记情态动词的特殊用法。应试高分注意1）情态动词一般疑问句的否定回答2）情态动词表推测的用法3）情态动词表能力/许可/义务的用法。09年命题特点1.-Dad,must I finish my homework t

14、oday？-No，you _.you may finish it tomorrow.(2008朝阳朝阳)A.neednt B.mustnt C.dont D.wont2.-May I put my bike here?(2008广安广安)-No,you _.You should put it over there.A.may not B.mustnt C.neednt解答锦囊解答锦囊掌握情态动词问句的回答：掌握情态动词问句的回答：May I?Yes,may.No,mustnt/cant.Must I?Yes,must.No,neednt/dont have to.1.-Is Mr.Brown

15、driving here？(2008安徽安徽)-Im not sure.He_come by train.A.may B.can C.need D.must2.-Whos that boy reading in the garden?Is it David?(2008重庆重庆)-It _be David.I saw him in the classroom just now.A.must B.cant C.may D.neednt3.Im sure this book_Li Leis,because there is his name on it.(2008吉林吉林)A.cant be B.m

16、ay be C.might be D.must be解答锦囊解答锦囊掌握推测用法掌握推测用法:肯定可能性由肯定可能性由Mustmaymight逐步递减逐步递减;Cant则用于则用于否定否定句、句、疑问疑问句。句。1.-Lisa,_you speak French？(2008南京南京)-Yes,but only a little.A.may B.can C.need D.must2.-_I use your mobile phone?(2008北京北京)-Certainly.Here you are.A.May B.Must C.should D.need3.-Mum,can I go to t

17、he movies today?(2008长沙长沙)-No,but you_finish your schoolwork first.A.can B.cant C.must D.neednt解答锦囊解答锦囊掌握基本用法掌握基本用法:can表能力表能力,may表许可表许可,must表义务。表义务。1.-Is Lucy knocking at the door?(2008长沙长沙)-No.It _be Lucy.She is in Japen.A.neednt B.must C.cant2.-Have you seen my glasses?I_find them.-sorry,I havent

18、seen them.(2008武汉武汉)A.cant B.shouldnt C.wont D.mustnt3.When traffic lights are red,we_stop and wait.(2007南京南京)A.may B.can C.must D.might4.-Must I Wait for here now?(2006沈阳沈阳)-No,you_.You may give it to me tomorrow.A.dont have to B.mustnt C.cant D.shouldnt用用法法归归纳纳needhave toshallshouldWillwouldcancould maymust能力能力许可许可可能性可能性可能性可能性许可许可必定必定(肯定句肯定句)必须必须(主观主观)推测（肯定句）推测（肯定句）必须（客观）必须（客观）不得不不得不必要（否定、疑问句）必要（否定、疑问句）建议建议义务责任义务责任主观愿望主观愿望请求希望请求希望