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1、1,Model Verb,2,定义,情态动词是一种本身有一定的词义,但要与动词原形及其被动语态一起使用，给谓语动词增添情态色彩，表示说话人对有关行为或事物的态度和看法，认为其可能、应该或必要等。,情态动词后面加动词原形。,注意,3,分类：,情态动词有四类：,只做情态动词：must,can(could),may(might),ought to,可做情态动词又可做实义动词：need,dare,可做情态动词又可做助动词：shall(should),will(would),具有情态动词特征：have(had,has)to,used to,4,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
2、,则在助动词之前,疑问句中,情态动词则在主语之前。,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?我能帮你吗？How dare you treat us like that！你怎能那样对待我们！,5,特点:,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。情态动词属非及物动词，故没有被动语态。,He could be
3、here soon.他很快就来。We cant carry the heavy box.我们搬不动那箱子。Im sorry I cant help you.对不起，我帮不上你。,6,The basic uses of Modal Verbs,7,一、can,could,1)表示能力（体力、知识、技能）。,Can you lift this heavy box?（体力）Mary can speak three languages.（知识）Can you skate?（技能）,此时可用be able to代替。（考点一）：Can只有一般现在时和一般过去；而be able to则有更多的时态。Ill
4、 not be able to come this afternoon.,当表示（考点二）“经过努力才得以做成功某事”时应用be able to，不能用Can。如：He was able to go to the party yesterday evening in spite of the heavy rain.,8,一、can,could,2)表示请求和允许。,-Can I go now?-Yes,you can./No,you cant.,此时可与may互换。在疑问句中还可用could,might代替，不是过去式，只是语气更委婉，不能用于肯定句和答语中。,-Could I come to
5、 see you tomorrow?-Yes,you can.(No,Im afraid not.)(考点),9,一、can,could,3)表示客观可能性（客观原因形成的能力）。,Theyve changed the timetable,so we can go by bus instead.This hall can hold 500 people at least.,4)表示推测（惊讶、怀疑、不相信的态度），用于疑问句、否定句和感叹句中。,Can this be true?This cant be done by him.对比：This must be done by him.How c
6、an this be true?,10,1.Can,Could 过去式；语气更委婉,Can 表示习惯能力，而be able to表示经过那里而做成了某事。2.在否定结构中，二者可以互换。,1.在否定、疑问句中表示“对过去发生行为的可能性猜测。2.在肯定句中表示“本来可以做而未做”,The door was lacked.She couldnt have been at home.（推测：）You could have been more careful.（但实事上没有更细致）,11,二、may,might,1)表示请求和允许。might比 may语气更委婉，而不是过去式。否定回答时可用（考点一
7、）cant或mustnt，表示“不可以，禁止”。,-Might/May I smoke in this room?-No,you mustnt.-May/Might I take this book out of the room?-Yes,you can.(No,you cant/mustnt.),用May I.？征徇对方许可时比较正式和客气，而用Can I.？在口语中更常见。,12,二、may,might,2）用于祈使句，表示祝愿。May you succeed!,3)表示推测、可能性（不用于疑问句）。might不是过去式，它所表示的可能性比may小。1He may/might be ve
8、ry busy now.2Your mother may/might not know the truth.,13,1.May,Might 过去式；语气更委婉,1.在否定、肯定句中表示对过去动作的推测“也许是”2.Might+have+p.p表示虚拟，表“劝告、责备之意。”,Eg.1.She may be still waiting for us.2.May I come in?3.May you have a happy holiday.,Eg.1.He might have spoken to her yesterday.（委婉推测）2.You might have told me ear
9、lier.（你或许可以早点告诉我，但实事上没有，有责备之意）,14,三、must,have to,1)表示必须、必要。,You must come in time.在回答引出的问句时，如果是否定的，(考点一)不能用mustnt（禁止，不准），而用neednt,dont have to（不必）.,-Must we hand in our exercise books today?-Yes,you must.-No,you dont have to/you neednt.,15,三、must,have to,2)must是说话人的主观看法，而have to则强调客观需要。Must只有一般现在时，h
10、ave to 有更多的时态形式。,He play isnt interesting,I really must go now.I had to work when I was your age.,3)表示推测、可能性（只用于肯定的陈述句）,Youre Toms good friend,so you must know what he likes best.Your mother must be waiting for you now.,16,1.Must,表示肯定的猜测,但只用于肯定句，而mustnt 表示“禁止、不准”,Must表示主观Have to表示客观需求Have got to 多见于
11、口语,3.must+have+p.p,对过去事情的肯定猜测。,Eg.The road is wet.It must have rained last night.,17,四、shall,should,1)shall 用于第一人称，征求对方的意见。,What shall we do this evening?Shall we go there by bus?,2)shall 用于(考点一)第二、三人称，表示说话人给对方的命令、警告、允诺或威胁。1.You shall fail if you dont work hard.(警告)2.He shall have me the book when I
12、 finish it.(允诺)3.He shall be punished.(威胁),18,1、Shall/should,shall/should+have+p.p ought to,表示本应该做而未做。,should 过去式 语气更委婉,Eg.You should have been five minutes ago.,2、,2、,19,五、will,would,1)表示请求、建议等，would更委婉,Will/Would you pass me the ball,please?,2)表示意志、愿望和决心。1.I will never do that again.2.They asked h
13、im if he would go abroad.,20,五、will,would,3)would表示过去反复发生的动作或某种倾向。would表示过去习惯时比used to正式，且没有(考点)“现已无此习惯”的含义。,1.During the vacation,he would visit me every other day.2.The wound would not heal治愈.创伤难以愈合 Would 后只能接表示动作的动词。used to 则还可以接表示状态的动词。（考点）He used to be a worker.,4)表示估计和猜想。It would be about ten
14、oclock when she left home.,21,Will/would,1、Would 后只能接表示动作的动词。,2、used to 则还可以接表示状态的动词。Eg.He used to be a worker.,22,used to和would的区别,1.都可以表示过去重复的习惯，used to 含有“过去怎样而现在却不这样了”的意思；而would则单纯表示过去的习惯性动作，常和often,everyday等连用。,He would take a walk near the forest in the evening.（现在可能散步也可能不散步了）,He used to take
15、a walk near the forest in the evening.（而现在不散步了）,23,1.She isnt what she used to be.她跟过去不一样了。（表示对比，不可用would）,2.There used to be a park.以前这里有一个公园。表示过去的状态，只能用used to，不可用would。,2.不能用would的情况,24,六、dare,need,1)dare作情态动词用时,常用于疑问句、否定句和条件从句中,过去式形式为dared。,How dare you say Im unfair?He darent speak English befo
16、re such a crowd,dare he?If we dared not go there that day，we couldnt get the beautiful flowers.,2)need 作情态动词用时,常用于疑问句、否定句。在肯定句中一般用must,have to,ought to,should代替。,1You neednt come so early.2.-Need I finish the work today?-Yes,you must./No,you neednt.,25,3)dare和 need作实义动词用时，有人称、时态和数的变化。在肯定句中，dare后面常接带
17、to的不定式。在疑问句和否定句中，dare后面可接带to或不带to的不定式。而need后面只能接带to的不定式。,1.I dare to swim across this river.2.He doesnt dare(to)answer.3.He needs to finish his homework today.,26,1、情态动词用于否定、疑问句；条件从句中。Eg.1.Dare you go here alone?2.How dare you do such follish things?3.I wont allow you to swim in the river,even if yo
18、u dare do it.,Dare/dared,2、做实意动词后加不定式。eg.I have never dared to tell him about it.,27,Need/needed,1、情态动词用于否定句，疑问句。,2、实意动词用法似dare,后加不定式。,3、need+not+have+p.p 表示“本来不需要做而做了。,28,可兼做行为动词的情态动词：need、dare,情态动词(+动词原形),行为动词,.,need,dare,1.无人称和数的变化;,2.尤其用于：,*否定句及疑问句中;,*在if/whether之后;,*或与hardly,never,no one,nobody
19、连用;,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 doneed to be done need doing,29,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 darent speak English before such a crowd,dare he?,30,Nobody need to be afr
20、aid of catching the disease.Nobody need be afraid of catching the disease.,These dishes needed be cleaned carefully.These dishes need to be cleaned carefully.These dishes need cleaning carefully.,31,七、should,ought to,1)should,ought to表示“应该”，ought to表示义务或责任，比should语气重。,1.I should help her because she
21、 is in trouble.2.You ought to take care of the baby.,2)表示劝告、建议和命令。should,ought to可通用，但在疑问句中常用should。,1.You should/ought to go to class right away.2.Should I open the window?.,32,七、should,ought to,3)表示推测should,ought to(客观推测),must(主观推测)。,1.He must be home by now.(断定他已到家)2.He ought to/should be home by
22、 now.(不太肯定)3.This is where the oil must be.(直爽)4.This is where the oil ought to/should be.(含蓄),33,Ought to,1、其否定式为ought not to,2、ought to+have+p.p 表示本来应该做而没有做到。ought+not+to have+p.p 表示本不来应该做而实际已做到,You ought to have come here early.You ought not to have cut away the trees around the old building.,34,
23、一，常见的情态动词有：can,could,may,might,must,shall,should,will,would,need,have to等 二，常见的情态动词的基本含义及用法,1.can/could_ _ _ _cant/couldnt_ _ _ _ 2.may/might_ _.may not_ 3.must_ _ 4.mustnt_ 5.neednt_ 6.have to_ _dont have to_ 7.will/would_ _ _ _ 8.should_shouldnt_ 9.May?的疑问句中否定回答用_或_ 10.Must?的疑问句中否定回答用_或_ 11.请你好吗？用
24、句型:_ 12.Shall I/we?表示 13.需要干某事_ _,能 会 可能 可以,不能 不会 不可能 不可以,可以 可能,可能不,必须 一定,不可以,不需要,不得不 必须,不需要,将 会 愿 要,应当,不应当,mustnt,cant,neednt,dont have to,Will/Would/could you(please)?,我/我们好吗？,need do sth need to do sth,14.情态动词后跟_,动词原形,35,三点说明,1、情态动词+v 表示对现在或将来动作的猜测。情态动词+have+p.p表示对过去动作的猜测。,2、情态动词的过去式与原形相比，多点礼貌，少点
25、冒昧，语气更为委婉。,3情态动词在一般疑问句中的回答：Can you sing?May I come in?Must I handin the book now?Need I finish it now?,36,典型错误,1.He mustnt be in the classroom.(),cant,2.You might leave the bag on the bag.(),might have left,3.You must have seen the film last week,havet you?(),didnt you,4.Li ming must have been to Ja
26、pan,didnt he?(),hasnt he,37,情态动词+完成式动词(指过去的动作或情况)1.may/might have done sth.可能做过(了)某事 2.cant/couldnt have done sth.不可能做了某事3.must have done sth.准是做了某事4.neednt have done sth.本不必做某事(实际上已做)5.could have done sth.本可以做某事(实际上没做)6.should have done sth.本应做某事(实际上没做)7.ought to have done sth.本应做某事(实际上没做)8.shouldn
27、t have done sth.本不应做某事(实际上已做)9.oughtnt to have done sth.本不应做某事(实际上已做),38,You could have done better,but you didnt try your best.2.He cant have been to that town.3.Can he have got the book?,He may not have finished the work.If we had taken the other road,we might have arrived earlier.,You must have s
28、een the film Titanic.He must have been to Shanghai.,（虚拟语气）,（推测）,（推测）,他可能没有做完那项工作,(条件虚拟）（我们也许会到的更早些）,（推测）,39,He should have finished the work by now。,You ought to/should have helped him.(but you didnt.)She shouldnt have taken away my measuring tape测尺,for I wanted to use it.,You neednt have watered th
29、e flowers,for it is going to rain.,40,表示能力:can,could,be able to*be able to 能用于各种时态。can/could 只能表示现在或过去的能力。*was/were able to:“设法做成某事”相当于 managed to do sth.succeeded in doing sth.。,1.表示能力、许可的情态动词的用法。,41,1.A computer _ think for itself;it must be told what to do.A.cant B.couldnt C.may not D.might not,2
30、.The fire spread through the hotel very quickly but everyone _ get out.A.had to B.would C.could D.was able to,A,D,42,3.They will _ run this machine on theirown in three months.can B.could C.may D.be able to4.That big cinema _ seat 2,000 people.A.can B.should C.ought to D.is able to,D,A,43,表示许可:may/m
31、ight,can/could*might,could 比较委婉,一般多用于疑问句.*can,may 表达的语言比较随便.*在以could,might 表示征询对方意见 或表示请求时，回答应相应使用can,may.,44,Can/May/Could I use your pen?,肯定简略回答：Yes,you can/may.Yes,please.,否定简略回答：No,you mustnt.Please dont.No,you may not.,45,5.Could I borrow your dictionary?Yes,of course you _.A.might B.will C.can
32、 D.should6.Might I watch TV after supper?Yes,you _.A.may B.must C.might D.can,C,A,46,2.表示否定的情态动词的用法:部分情态动词的否定式是情态动词中的考点之一,mustnt neednt cant may not shouldnt,不准,禁止 没必要(=dont have to)不能;不可能不可以;可能不不应该(=ought not to),47,7.You _ return the book now.You can keep it till next week if you like.cant B.mustn
33、t C.neednt D.may not8.Johnny,you _ play with the knife,you _ hurt yourself.A.wont;cant B.mustnt;may C.shouldnt;must D.cant;shouldnt,C,B,48,9.-Will you stay for lunch?-Sorry,_.My brother is coming to see me.A.I mustnt B.I cant C.I neednt D.I wont10.-May I pick a flower in the garden?-_.A.No,you needn
34、t B.Not,please.C.No,you mustnt D.No,you wont,B,C,49,情态动词：shall,will 的多种意义:,shall/will+动词原形:,*shall 可表示必须、命令、警告或征询意见.,*will 可表示意愿、常出现的动作、在疑问句 中表示请求和建议.,*均可表示将来。过去时为 should,would.,3.,50,shall用在主语是第一和第三人称的疑问句中表示征求对方的允诺；,Shall I open the window?Shall he come in or wait outside?,will用在主语是第二人称的疑问句中,表示“请求”
35、,Would you pass the salt,please?Will you please pass the salt?,will用于主语是各人称的陈述句中,表示“意愿、倾向”-The phone is ringing.-Ill get it.,51,“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,52,11.He _ be punished if he diso
36、beys.如果他不服从,就要受到惩罚.12.We are not going to quarrel at all if you _ only let me speak.只要你让我说话,我们根本就不会吵架.13.-Sir,_ he go or stay?-Let him go.A.will B.shall C.might D.could,shall,will,B,53,14.The door _ open.这门经常打不开.15.Ronald _ stay in his small garden for a long time every day in the past.A.could B.mig
37、ht C.should D.would16.You _ have the book after I read it.我看完以后一定把这本书给你.,wont,D,shall,54,4.情态动词短语的使用:,would like to dowould rather dowould rather+sb.+did sth.would prefer to do.had better do.,55,改错:1.Would you like having some tea?2.Id prefer going to the lecture this evening.3.Id rather you to go t
38、o the meeting.4.He would rather to die than to give in.5.Youd better to have your hair cut today.,Would you like to have some tea?,Id prefer to go to.,you went to.,He would rather die than give in.,Youd better have.,56,5.表示推测情态动词的重要用法.,1.You must be Mr Smith-I was told to expect you here.2.He must h
39、ave known what we wanted.3.We may have read the same report.4.He cant have slept through all that noise.5.Theres someone outside-who can it be?6.What can they be doing?7.These pills might help to cure your disease.8.You could be right,I suppose.,57,表示推测情态动词的重要用法.,肯定的推测可能的推测否定的推测疑问的推测,must,对将来 对现在 对过
40、去,情态动词,may,mightcould,cant,couldnt,can,could,+V.+V.+have done常见must be+be doing,+V.+V.+have done+be doing 可以用not表示“可能不”,+V.+V.+have done+be doing,+V.+V.+have done+be doing,58,情态动词must，can，could，may，might都可用来表示推测,1.must所表示的可能性最大，最有把握，意为“一定”。,2.can和could主要用于否定句和疑问句中，cant或couldnt 表示“不可能”,3.may 和 might表
41、示现在或将来可能发生的动作或情况，主要用于肯定句中，might相对于may 来说，表示的可能性更小一些。,注意：,1).表示猜测，can/could一般不用于肯定句中，除非是“经验之谈”。,如：Anybody can make mistakes,59,如：(正)Can Could it be cloudy tomorrow？(误)May Might it be cloudy tomorrow？,1.Mary _ be in Paris，for I saw her in the town only a few minutes agoAmustnt Bcant Cshouldnt Dmay not
42、,2.Peter come with us tonight，but he isnt very sure yetAmust Bmay Ccan Dwill,2)may和might都不用于疑问句中。,60,3.Are you coming to Jeffs party Im not sure I go to the concert insteadAmust Bwould Cshould Dmight,4.It _ last night，for the ground was wet this morning Amust have rained Bmay have rained Cmust rain
43、Dmight rain,61,should也可以用来表示“推测”，意为“可能；该”,相当于be expected to。往往指具有一定的客观根据或根据推理对现在某事发生的“可能性”进行描述，语气上不如must强。,1.Will Mr Wang offer us a hand?He _ be glad toHe never refused our request Acan Bmust Cmay Dshould,62,2.When can I come for the photos?I need them tomorrow afternoon.They _ be ready by 12：00 Ac
44、an Bshould Cmight Dneed,3.Its nearly seven oclockJack _ be here at any moment Amust Bneed Cshould Dcan,63,解答情态动词表示猜测的试题时，一要清楚被猜测的时间，二要清楚有无客观事实根据。若有客观事实根据，则无论是肯定还是否定的猜测，猜测语气最强且符合时间要求的为最佳答案；若无客观事实根据，纯凭主观臆断则猜测语气最弱且符合时间要求的为最佳答案。情态动词表示猜测时语气从强到弱的顺序是：must，should，can，may，could，might。,64,不同的“肯定”程度可按下列层次排列：He
45、 is at home.(事实)He must be at home.（非常肯定的推断）He could be at home.（很可能）He ought to be at home.（很可能）He may be at home.（仅仅可能而已）He might be at home.（或许,非常不确定）He might not be at home.（也许不在家）He may not be at home.（比might可能）He couldnt be at home.（很可能不在家）He cant be at home.（一定不在家）He isnt at home.（事实）,65,1.I
46、thought you _like something to read,so I have brought you some books.A.may B.might C.would D.must 2.Where is my pen?I _it.A.might lose B.would have lost C.should have lost D.must have lost3.I didnt hear the phone.I _asleep.A.must be B.must have been C.should be D.should have been,B,D,B,66,4.-There w
47、ere already five people in the car,but they managed to take me as well.-It _a comfortable journey A.cant be B.shouldnt be C.mustnt have been D.couldnt have been 5.Its nearly seven oclock.Jack _be here at any moment.A.must B.need C.should D.can,D,D,67,6.用于虚拟语气的情态动词:,should/ought to have done shouldnt
48、/oughtnt to have done might/could have doneneednt have done,本应该做（但事实没做）本来不应该做（但事实却做了）本来可以做（但事实没这样做）本来不需要做（但事实却做了）,68,1.I was really anxious about you.You _ home without a word.A.mustnt leave B.shouldnt have left C.couldnt have left D.neednt leave2.There was a lot of fun at yesterdays party.You _ com
49、e,but why didnt you?A.must have B.should C.need have D.ought to have,B,D,69,3.I stayed at a hotel while in New York.-Oh,did you?You _ with Barbara.A.could have stayed B.could stayC.would stay D.must have stayed4.I told Sally how to get here,but perhaps I _ for her.had to write it out B.must have wri
50、tten it outC.should have written it out D.ought to write it out,A,C,70,We _ last night,but we went to the concert instead.No wonder we failed in the quiz this morning.A must have studiedB might studyC should have studiedD would study,71,2.Jenny _ have kept her word.I wonder why she changed her mind.
