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1、Unit 2 Sports events,Modal verbs,Grammar and usage,Warming-up exercises,He _ speak English fluently.(表能力)2.You _ work hard to win the gold medals.(表责任/义务)3._we do some exercises this morning?(表征求对方意见)4.-Might I watch TV after supper?-Yes,you _.A.may B.must C.might D.could5.-May I pick a flower in th
2、e garden?-_.A.No,you need B.No,please C.No,you mustnt D.No,you wont,must,can,Shall,A,C,一情态动词的语法特征 情态动词表示说话人对某一动作或状态的态度，可以表示“可能”、“可以”、“需要”、“必须”或“应当”等之意。情态动词没有人称和数的变化。情态动词不能单独作谓语动词用，必须和不带to的不定式连用构成谓语动词。,Modal verbs:general introduction,二情态动词的语法功能 We can use modal verbs to talk about:,ability,certainty
3、,permission,obligation,make requests,make suggestions,make offers,give advice,能力,义务,责任,确定,允许,提出请求,提出建议,提供帮忙,提出忠告,Modal verbs:general introduction,情态动词,1.can could be able to,2.shall,4.may might,三常见情态动词的基本用法,3.must have to,7.will would,5.need dare,6.ought to should,8.情态动词+have done,can表示能力,could是其过去式
4、,Some of us can use the computer now,but we couldnt last year.,1.情态动词can,could和be able to的用法,表示“客观的可能性”,*吸烟往往会导致癌症。,Smoking can cause cancer.,*It can be very cold here in winter.,这的冬天有时会很冷。,E.g:-Could I use your pen?(语气委婉)-Yes,you can.No,you cant/mustnt.,表示“请求”,主要用于疑问句中,表示委婉语气,过去式could 比can更加委婉。肯定回答
5、时,常用原形can,不可再用过去式could。,表示请求或许可,-Can I go now?-Yes,you can.,表示推测,常用于疑问句和否定句中,This cant/couldnt be done by him.,He couldnt have been to the city.,区别 can 与be able to(1).be able to表示能力,有人称和数的变化,可用于各种时态;(2).只表示能力时,can=be able to(3).was/were able to更侧重于“过去做成了某事”=managed to do sth.=succeeded in doing sth.
6、,E.g:*He was able to swim across the river before the ship sank.,【Practice】*He managed to get the radio repaired without any help.=He _/_ the radio repaired without any help.,was able to get,succeeded in getting,2.shall用法 shall常用于第一,三人称疑问句中,表示征求对方意见,用于二、三人称陈述句中表示决心、命令、警告、允诺、威胁、强制等语气。Shall he clean t
7、he blackboard for you?Take it easy.You _be offered a job in this company.Mike _spare no effort to study.(1)“The interest _be divided into five parts according to the agreement made by both sides.”declared the judge.A.may B.should C.must D.shall,shall,shall,D,表“法律法规等文件中表示义务或规定”,(2)-Excuse me,but I wa
8、nt to use your computer to type a report.-You_ have my computer if you dont take care of it.A.shant B.might not C.neednt D.shouldnt(3)The boss said to the secretary,“If you work well,you _ have a rise.”A.must B.ought C.shall D.would,A,C,表“警告”,表“允诺”,3.情态动词must和have to的用法:“must”与“have to”都表示“必须,不得不”,m
9、ust:主观愿望have to:客观需求,有时态,人称和数的变化.,Ex:,*The train leaves at 7 oclock.I _(must/have to)go now.,*I dont like my watch.I _(must/have to)buy a new one.,have to,must,E.g:-你现在就得回家吗？-是的,我现在就得回家。不,我现在不需要回家。-Must you go home now?(必须),在疑问句中“must”表示“必须”的回答形式 肯定“Yes,sb.must.”;否定“No,sb.neednt.”或“No,sb.dont(doesnt
10、)have to.”*dont have to=neednt 没必要,-Yes,I must./No,I neednt.=I dont have to.,否定句中用cant/couldnt表示对现在的肯定推测 must do 表示对过去的肯定推测 must have done肯定已经做了某事,must表示肯定的推测,只能用于肯定句指“一定,肯定”;,Practice*你现在一定困了/不困。,He must have watched the football match last night.,You must be/cant be sleepy now.,*你现在一定困了,不是吗?,*他昨晚一
11、定看足球比赛了。,You must be sleepy now,arent you?,*He must have watched film last night,_?,*He must have watched film,_?,A.hasnt he B.mustnt he C.didnt he D.hadnt he,C,A,mustnt 表示“不准、禁止”,*你们不准在学校吸烟。,You mustnt smoke at school.,must有时表示“偏要”,含“责备,抱怨”之意,(1)我已经跟你讲过很多遍了,为什么你偏要 在课堂上讲话呢？(2)现在已是午夜了,你偏要这个时候弹 钢琴吗？,I
12、 have told you many times._?,It is midnight._?,Must you play the piano now,Why must you talk in class,4.may/might(1)表示“许可或请求许可”时:might,比较委婉,一般多用于疑问句;might表示征询对方意见或表示请求时,回 答应相应使用 may;表示允许(肯定句)和请求(疑问句);若回答 表示“不可以/不准”时,一般用mustnt.E.g:-May/Might I use your dictionary?-Yes,_./No,you _.,may/can,mustnt,(2)表
13、猜测时,“may,might”能用于陈述句中,有“或许,大概”之意.may的可能性较大,might的可能性最小;,(3)may可以表示“祝愿”,might不能这样用E.g:*希望上帝保佑你!,May God bless you!,*Rose may be busy now.*Rose might have returned home,but Im not sure.,*但愿你快乐!,May you be happy!,Practice:,1、-Might I watch TV after supper?-Yes,you _.A.may B.must C.might D.could2、-Wher
14、e is my dictionary?I remember I put it here yesterday.-You _it in the wrong place.A.must put B.should have put C.might put D.might have put,A,D,5.should&ought to,Should&ought to含义相近，都可表“责任，义务”常可互换。区别在于:ought to常指按义务，法律，规定等“应当”。Should则指主观上按道理应该。ought to 比should语气更强烈,should表义务，按道理“应该”,含劝告,建议语气,You sho
15、uld be polite to your teachers.,表主观上推测,“照理应该”,The film should be very good as it is starring first-class actors.,表意外或惊讶语气,译竟然,You should wear slippers(拖鞋)at work!,ought to,表义务,应该(因责任义务,法律规定等做),He is your father.You ought to take care of him.,表推测,应该,He ought to know my telephone number.,6.will,would,
16、表意愿或意志,决心,would为过去时,I will not do that again.,表征求意见或提出请求,常用于疑问句中,would语气更委婉.,Will/Would you pass me the book?,表经常性,习惯性动作,“总会”=used to The old man would have a smoke under a big tree every afternoon.表功能,“能,行”The machine wont work.,7.need/dare,可兼做行为动词的情态动词：need、dare,-Need I tell him everything?-Yes,yo
17、u must.-No,you neednt/dont have to.,情态动词(+动词原形),行为动词,.,need,dare敢,1.无人称和数的变化;,2.尤其用于：,*否定句及疑问句中;,3.常以neednt 和darent 的形式出现;,4.dare有其过去时dared.,多用于肯定句;need to do dare to do,1.判断正误:,How dare you say such a thing?How dare you to say such a thing?,He darent to speak English before such a crowd,did he?He d
18、arent speak English before such a crowd,dare he?,Exercises,neednt have done 过去没有必要做某事而实际上却做了(虚拟）can/could(not)have done 过去本可以(不)做某事却没做(做了)（虚拟）过去可能已经做了某事（对过去的推测）may/might have done 过去可能已经做了某事（对过去的推测）,8.情态动词+have done表示对已经发生事情推测、责怪、后悔、遗憾等。,must have done,should/ought to have done,肯定已经做了某事（对过去的推测）,本应该做
19、某事却没做(虚拟）应该已经做了某事（对过去的推测）would have done本来会做某事，却没做(虚拟）,表示推测(可能性)时,按语气强弱,强,弱,must,may,cant,couldnt,can,could,might,should,ought to,1.The weather turned out to be fine yesterday.I_ the trouble to carry my umbrella with me.A.should have taken B.could have taken C.neednt have taken D.mustnt have taken2.
20、-Ill tell Mary about her new job tomorrow.-You _her last week.A.ought to tell B.would have told C.must tell D.should have told,C,D,Practice,3.She _ have left school,for her bike is still here.A.cant B.wouldnt C.shouldnt D.neednt4.-I cant find my purse anywhere.-You _ have lost it while shopping.A.ma
21、y B.can C.should D.would5.-I stayed at a hotel while in New York.-Oh,did you?You _with Barbara.A.could have stayed B.could stay C.would stay D.must have stayed,A,A,A,What sort of house do you want to have?Something big?-Well,it _ be bigthats not important.A.mustnt B.neednt C.cant D.wont2.改错 Mr.Li mu
22、stnt have gone to Shanghai because I saw him a few minutes ago.,B,Back,cant,must表推测只用于肯定句,否定句中表推测用cant;mustnt 指“禁止、不准”,1.He said that the bike _ stolen and that he_ have to telephone the police.A.was,would B.has,will C.has been,will D.had been,would not2.Mr.Bush is on time for everything.How _ it be
23、 that he was late for the opening ceremony?A.can B.should C.may D.must,D,Back,A,1.1.It has been announced that candidates _ remain in their seats until all the papers have been collected.A.can B.will C.may D.shall 2.You cant imagine that a well behaved gentleman _ be so rude to a lady.A.might B.need
24、 C.should D.would,D,C,Back,1.Tom,finish your homework first,or you _ watch TV!A.shant B.couldnt C.neednt D.may not2.-She looks very happy.She _(must/might)have passed the exam.-I guess so.Its not difficult after all.,A,Back,must,1.-Could I borrow your dictionary?-Yes,of course you _.A.might B.will C
25、.can D.should2.Hearing the steps of the police,the thief _ move at all.A.dares not B.dared not to C.didnt dare to D.not dare,C,C,Back,1.-Where is my dictionary?I remember I put it here yesterday.-You _it in the wrong place.A.must put B.should have put C.might put D.might have put 2.-Is John coming b
26、y train?-He should,but he _not.He likes driving his car.A.must B.can C.need D.may,D,D,Back,表对过去可能性的推测。,1.Mike,look at the time._you play the piano at such a late hour?A.Must B.Can C.May D.Need 2.She is already two hours late.What _to her?A.may have happened B.can have happened C.should have happened
27、 D.must happen,A,Back,B,1.If it were not for the fact that she _sing,I would invite her to the party.A.couldnt B.shouldnt C.cant D.might not,C,2.It is recommended that passengers _ keep their cell phones on when the plane is landing.not B.need not C.could not D.would not,Back,cant 表能力,此处表示她本身能唱歌的一个客
28、观事实。,A,1.I didnt hear the phone.I _asleep.A.must be B.must have been C.should be D.should have been2.My suggestion is that Tom_ abroad and he stay here until the project completes.send B.should not send C.be sent D.not be sent,B,Back,D,1.A _ candle _ the faces of everybody in the room.They all looke
29、d tired.A.lit,lit up B.lit up,lit C.lighted,lit up D.lighted,lit2.There is a party tonight _ our new president,and I am _ to be invited.A.in honor;honored B.in place of;of great honorC.in great honor;in favor of D.in honor of;honored,Back,D,C,Homework,Review the modal verbs we learnt today;2.Finish Step III Practice of Learning plan 4-5.,
