1、情态动词情态动词常用的情态动词常用的情态动词can（could）may（might）shall（should）will （would）mustdare（dared）need have to ought to be able toused toThe features（特点（特点)of the modal verbs:1.情态动词本身有词义情态动词本身有词义,但词义不完全但词义不完全.2.不能单独作谓语不能单独作谓语,只能和动词原形一起构成谓语只能和动词原形一起构成谓语.3.情态动词没有人称和数的变化情态动词没有人称和数的变化(除除“have to”).4.没有没有不定式不定式、V-ing、V-
2、ed 形式形式.He can/could/must/may/might/shall/should/need/dare/dared/will/would/ought to/used to+work in that factory.He has to go home now.He had to look after his sick mother.在情态动词的使用中在情态动词的使用中,我们要注意以下考点我们要注意以下考点:1.情态动词的基本用法。情态动词的基本用法。2.情态动词情态动词表推测表推测的用法。的用法。3.情态动词情态动词+have done 的用法。的用法。1.表表“能力能力”can,
3、could的用法的用法1.I can/am able to swim.2.I could/was able to climb a tree when I was a child.3.I will be able to swim next week.4.The fire spread through the hotel very quickly but everyone was able to get out.1.can 表示现在的能力表示现在的能力2.could表示过去的能力表示过去的能力3.be able to 表能力，可用于多种时态表能力，可用于多种时态4.be able to 强调成功地
4、做了某事强调成功地做了某事2.表“请求请求,许可许可”could用来表示请求的时候比用来表示请求的时候比can 更委婉更委婉Can you help me with my English?He said I could borrow his bike.Could I use your bike?Could I borrow your dictionary?Yes,of course you _A.might B.will C.can D.should3.表“可能性可能性”can,could 用在用在肯定句肯定句中表示理论上的可能性，中表示理论上的可能性，“经验之谈经验之谈”As a human
5、 being,anyone can make a mistake.can,could用在用在疑问句疑问句中表推测中表推测,表示可能性表示可能性 Can she be in the classroom?can,could用在用在否定句否定句中表推测，翻译成中表推测，翻译成“不不可能可能”We thought the story couldnt be true.1.Mary _ be in Paris，for I saw her in the town only a few minutes ago A mustnt B cant C shouldnt D may not2.My MP4 playe
6、r isnt in my bag.Where _ I have put it?A.can B.must C.should D.would1.表表“询问询问”(might比用比用may更客气更客气.)May I?(=Can I?)Might I?(=Could I?)May I borrow your book?may与与might用法用法May I pick a flower in the garden?_.A.No,you neednt B.Not,please.C.No,you mustnt D.No,you wont注意：注意：may I?的答语的答语.肯定肯定:Yes,you may.
7、否定否定:No,you mustnt (语气强硬语气强硬)No,you may not.或或 No,youd better not.2.表表“许可许可”You may take the boy thereHe said that I might use his telephone.Might I watch TV after supper?Yes,you _.A.may B.must C.might D.could3.表表推测推测，表示主观上的推测，表示主观上的推测，“可能，可能，也许也许”，不用于疑问句不用于疑问句,might比比may的可能性更小的可能性更小She may not like
8、 this place.Im afraid he might not like this place.Peter come with us tonight，but he isnt very sure yet A must B may C can D will 1.must 表示主观上的表示主观上的必须必须，应该应该，没有时态，没有时态变化。变化。You must do everything as I do.注意注意:Must I finish my homework today?Yes,you must.No,you neednt./No,you dont have to.must 的用法的用
9、法“必须必须、不得不不得不”must表示的是说话人的主观看法。表示的是说话人的主观看法。have to 表示的是客观需要。（表示的是客观需要。（是由于某种外是由于某种外界（客观）原因而界（客观）原因而“必须必须”，“不得不不得不”做某做某事，也可表示经常的或习惯性的事事，也可表示经常的或习惯性的事“必须必须”做。）做。）I have to be at my office every evening.注意：注意：1.have to的否定形式的否定形式dont have to表示表示不必不必。2.have to可用于多种时态中。可用于多种时态中。1.In crowded places like a
10、irports and railway stations,you_ take care of your luggage.A.can B.may C.must D.will2.Must he come to sign this paper himself?Yes,he _.A.need B.must C.may D.will 2.must表示肯定的推测。表示肯定的推测。The light is still on,so he must be at home.Look at his new car.He _ have a lot of money.A.should B.shall C.may D.m
11、ust3.must表示表示“一定要一定要”、“坚持坚持”“偏要偏要”、“偏偏偏偏”。表。表示与说话人的愿望相反示与说话人的愿望相反.If you must go，at least wait till the storm is overMust you make so much noise？你偏要弄出那么？你偏要弄出那么多噪音？多噪音？May I smoke here?If you _,choose a seat in the smoking section.A.should B.could C.may D.must4.mustnt 表示表示禁止禁止做某事。做某事。You mustnt smok
12、e in the office.When I was young,I was told that I _ play with matches.A.wouldnt B.neednt C.mustnt D.darentshall作作助动词助动词，用于第一人称，表示将来，用于第一人称，表示将来，should 是是shall 的过去式的过去式We shall start for Beijing tomorrow.shall作作情态动词情态动词1：用于用于第一人称第一人称和和第三人称第三人称，表示征求对，表示征求对方意见或请求指示方意见或请求指示 Shall we begin our lesson?Sh
13、all I/she sit here?shall与与should用法用法-Sir,_ he go or stay?-Let him go.A.will B.shall C.might D.could2:shall 用于用于第二第二、三人称三人称，表示，表示允诺、警告、允诺、警告、威胁、命令、决心威胁、命令、决心等。等。You shall have a nice present for your birthday.You shall be sorry for what you have done.When he comes in nobody shall say a word.Nothing s
14、hall stop us from carrying out this plan.(允诺允诺)(警告警告)(命令命令)(决心决心)1.It has been announced that candidates(候选候选人人)_ remain in their seats until all the papers have been collected.A.can B.will C.may D.shall2.Excuse me,but I want to use your computer to type a report.You _ have my computer if you dont t
15、ake care of it.A.shant B.might not C.neednt D.shouldnt3).shall用于用于条约，规定，规章条约，规定，规章等文件等文件中，表示一种义务，多用于第三人称中。中，表示一种义务，多用于第三人称中。“The interest（利益）（利益）_ be divided into five parts,according to the agreement made by both sides.”declared the judge.A.may B.should C.must D.shall 1.should=ought to 表示劝告，建议，意表示劝
16、告，建议，意为为“应该应该”，ought to 语气更强些，强调语气更强些，强调“有责任，有有责任，有义务做义务做”A:Ill start the work tomorrow.B:I think you should start today.C:No,you ought to start at once.(语气更强）语气更强）should/ought to的否定形式表示的否定形式表示“不应该不应该”Children shouldnt smoke.Hows your tour around the North Lake?Is it beautiful?It _ be,but it is now
17、heavily polluted.A.will B.would C.should D.mustWhat time ought I _?Aarrived Barriving Carrive Dto arriveHe _ speak to his mother like that.Aought not to Bdoesnt ought to Cnot ought to Dought to not2.should 可表示说话人的感情如可表示说话人的感情如“惊奇惊奇”“愤怒愤怒”“失望失望”“不满不满”等等.翻译为翻译为“竟然，竟然，居然居然”I dont believe that the littl
18、e girl should speak two different languages!我不相信这个小女孩竟然能说两种不同的语言！我不相信这个小女孩竟然能说两种不同的语言！I cant believe my eyes.Such well-educatedgentleman _ behave like this!A.would B.should C.can D.must3.should表表推测推测,意为意为“可能；该可能；该”,相当于相当于be expected to。往往。往往指具有一定的客观根据指具有一定的客观根据或根据推理对现在某事发生的或根据推理对现在某事发生的“可能性可能性”进进行描述
19、，语气上不如行描述，语气上不如must强。强。Mr.Black must be home by now.Mr.Black ought to/should be home by now.布莱克先生现在一定到家了。（肯定）布莱克先生现在一定到家了。（肯定）布莱克先生估计是到家了。（不能肯定）布莱克先生估计是到家了。（不能肯定）2.When can I come for the photos?I need them tomorrow afternoon.They _ be ready by 12：00 A can B should C might D need3.Its nearly seven o
20、clock Jack _ be here at any moment A must B need C should D can1.Will Mr.Wang offer us a hand?He _ be glad to He never refused our request A can B must C may D should 1.will 作情态动词用时在陈述句中可作情态动词用时在陈述句中可用各人称作主语用各人称作主语,表示其表示其“意志意志”“意意愿愿”“决心决心”等等.I will never do that again.I will give up smoking.Dont for
21、get to bring my new books tomorrow afternoon.No,I.A.dont B.cant C.wont D.couldntwill 和和would 的用法的用法2.will 在疑问句中用第二人称作主语在疑问句中用第二人称作主语,表表示说话人向对方示说话人向对方提出请示或询问提出请示或询问.不如不如would委婉委婉Will/Would you pass me the book?Will he pay for me?Would you like to come with us?3.will 有时表示一种习惯动作或状态或自然规有时表示一种习惯动作或状态或自然规
22、律律.(表示习惯表示习惯,经常性经常性,倾向性倾向性)惯于惯于,总是总是(会会),终归是终归是。Boys will be boys.男孩终归是男孩。男孩终归是男孩。Matches will not strike if they are damp.火柴潮湿就擦不着。火柴潮湿就擦不着。The door _ open.这门经常打不开。这门经常打不开。wont1.would 可用于各人称可用于各人称,表示过去时间的表示过去时间的 “意志意志”“愿望愿望”和和 决心决心”.2.would 表示说话人本身的表示说话人本身的“意志意志”或向对或向对方提出方提出“请求请求.3.would 还可以表示过去习惯发
23、生的动作还可以表示过去习惯发生的动作.He used to take a walk near the forest in the evening.（现在可能散步也可能不散步了）现在可能散步也可能不散步了）used to表示过去常常发生的动作或存在的习惯，表示过去常常发生的动作或存在的习惯，但现在已不复存在了。但现在已不复存在了。He would take a walk near the forest in the evening.（而现在不散步了）而现在不散步了）Ronald _ stay in his small garden for a long time every day in the
24、 past.A.could B.might C.should D.would1.作为情态动词用，常用在否定句和疑问句中。作为情态动词用，常用在否定句和疑问句中。Dare(need)+S+VS+darent(neednt)+VI darent walk through the forest at night.Dare you walk through the forest at night?You neednt return the book now.Need he do it all at once?可兼做行为动词的情态动词：可兼做行为动词的情态动词：need、dare dare,need 的
25、用法的用法2.作实义动词用，常用在肯定句中作实义动词用，常用在肯定句中,有人称、有人称、时态、和数的变化时态、和数的变化He needs to go there himself.He has grown up,we dont need to worry about him.3.Sth(sb)need(want,require)+doing/to be done The house needs cleaning/to be cleaned The boy needs sending to the hospital at once.句句型型时态时态情态动词情态动词dare实义动词实义动词 dare
26、肯肯定定句句现在时现在时 dare dodare/dares to do过去时过去时 dared dodared to do否否定定句句现在时现在时darent/dare not dodo/does not dare(to)do过去时过去时 dared not do did not dare(to)do疑疑问问句句 现在时现在时 Dare he do?Do you/Does he dare(to)do?过去时过去时 Dared he do?Did he dare(to)do 1.I wonder how he _ that to the teacher.A.dare to say B.dare
27、 saying C.not dare say D.dared say2.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 off3.The dog hibernate(冬眠冬眠)in winter.A.dont need B.doesnt need to C.needs not to D.needs not注意对注意对need问句的回答问句的回答:-Need I finish the work t
28、oday?-Yes,_.No,_.No,_.you mustyou needntyou dont have toneednt 对其它情态动词的回答对其它情态动词的回答:-Shall I tell John about it?-No,you _.-Must we do it now?-No,you _.neednt(dont have to)neednt(dont have to)二、二、情态动词表推测情态动词表推测1.肯定的推测肯定的推测 一般用一般用must,should,may（might）或）或could（不用（不用can），其中，），其中，_的语气最强，的语气最强，译为译为“肯定肯定”
29、、“准是准是”、“想必是想必是”；_的语气次之，译为的语气次之，译为“很可能很可能”、“应该应该”，指按常理推测；，指按常理推测；_的语气最弱，译为的语气最弱，译为“也许也许”、“可能可能”。mustshouldmay（might），），could-Are you coming to Jeffs party?-Im not sure.I _ go to the concert instead.A.mustB.wouldC.shouldD.might-Hi,tom.Any idea where Jane is?She _ in the classroom.I saw her just now.A
30、.shall be B.will be C.must be D.can beAccording to the speed,the car _ arrive at Shanghai before it gets dark.A.shall B.should C.can D.need 注：注：can 有时也用于肯定句中表示推测，有时也用于肯定句中表示推测，主要用于表示理论上的可能性主要用于表示理论上的可能性(即从理论上看是可即从理论上看是可能的，但实际未必会发生能的，但实际未必会发生)，或表示，或表示“有时有时”之意。之意。如：如：Even experienced teachers can make
31、 mistakes._She can be very unpleasant._Food poisoning can cause death._即使是有经验的教师也可能出错。即使是有经验的教师也可能出错。她有时很令人讨厌。她有时很令人讨厌。食物中毒可导致死亡。食物中毒可导致死亡。It is usually warm in my hometown in March,but it _ be rather cold sometime.A.must B.can C.should D.wouldPeter _ be really difficult to deal with at times even t
32、hough he is a nice person in general.A.shall B.should C.can D.mustat times:有时；偶尔有时；偶尔2.否定推测分为两种情况：否定推测分为两种情况：1）语气不语气不是是很肯定时，常用很肯定时，常用may not,might not，译为，译为_ 2）否定语气较强时，则用）否定语气较强时，则用_，译为译为“根本不可能根本不可能”、“想必不会想必不会”，可能不、也许不可能不、也许不can tMale customers_ not like the design of the furniture.A.must B.shall C.
33、may D.need Isnt that Anns husband over there?No,it _ be him Im sure he doesnt wear glasses.A.cant B.must not C.wont D.may not3.疑问句中的推测，疑问句中的推测，往往用can或could。Mr.Bush is on time for everything.How _ it be that he was late for the opening ceremony？A.can B.should C.may D.must 4.对已发生事情的推测。对已发生事情的推测。肯定推测常用
34、肯定推测常用“must,may,might+完成式完成式”；否定和疑问推测常用否定和疑问推测常用“can,could，may,might+完成式完成式”。must have done:_cant/couldnt have done:_may/might have done:_想必一定做了某事想必一定做了某事不可能做了某事不可能做了某事可能可能/或许已经或许已经 Guess what!I have got A for my term paper.Great!You _ read widely and put a lot of work into it.A.mustB.should C.must
35、have D.should have My MP4 player isnt in my bag.Where_I have put it?A.can B.must C.should D.would I cant find my purse anywhere.-You _ have lost it while shopping.A.may B.can C.should D.would 1.must+have+过去分词，表示现在对过去分词，表示现在对过去过去事物的推测。事物的推测。三三情态动词情态动词+have+P.P.He must have told my parents about it.他一
36、定把这件事情告诉我父母亲了。他一定把这件事情告诉我父母亲了。Its six oclock already,we must have been late again.已经六点钟了，我们一定又迟到了已经六点钟了，我们一定又迟到了2.cant/couldnt+have+P.P表示对表示对过去过去某某事的事的否定否定猜测猜测He couldnt have been to that town.3.may(might)+have+P.P,表示对表示对过去过去事事情的猜测情的猜测,认为某事认为某事“可能可能”发生发生.(might比比may更含蓄更含蓄,或更不肯定或更不肯定.)He may(might)ha
37、ve played electric game on TV the whole night.For he looks very sleepy.could+have+P.Pa.表示本来能做得到表示本来能做得到,但事实上未做到但事实上未做到He could have finished the task on time,but the heavy snow came.can/could+have+P.Pb.表示对过去事情的推测表示对过去事情的推测(只用于疑只用于疑问句问句)He didnt come back last night.What could have happened to him.4.
38、should/ought to+have+P.P.过去本该做过去本该做，而事实上却没有做，而事实上却没有做，表，表“责备责备”或或“惋惋惜惜”should not /ought not to+have+P.P.过去本过去本不该做，而事实上却做了不该做，而事实上却做了，表，表“责备责备”或或“惋惜惋惜”The plant is dead.I should have given it more water.You should not have left your baby alone in the house.5.neednt+have+P.P.表示表示本来不必本来不必做，但做了做，但做了.Sh
39、e need not have attend the meeting yesterday,but she did.(她昨天本不必参加会议，可她参加了她昨天本不必参加会议，可她参加了.)1.The river is rising.It _last night.A.must be raining B.must rain C.might have rained D.must have rained2.I didnt hear the phone.I _asleep A.must be B.must have been C.should be D.should have been3.-There we
40、re already five people in the car,but they managed to take me as well.-It _a comfortable journeyA.cant be B.shouldnt be C.mustnt have been D.couldnt have been4.You yesterday if you were really serious about your work.A.ought to come B.ought to be comingC.ought to have come D.ought have come 5.You _
41、all these boxes yourself.The shop would have delivered them if you had asked a shop assistant.A.didnt need to carry B.neednt have carried C.neednt carry D.didnt need carry6.Mr.White _ at 8:30 for the meeting,but he didnt show up.A.should have arrived B.should arrive C.should have had arrived D.shoul
42、d be arriving7.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 told1.Helen _ go on the trip with us,but she isnt quite sure yet.A.shall B.must C.may D.can 2.-Ive taken someone elses green sweater by mistake.-It _ Harrys.He alwa
43、ys wears green.A.has to be B.will be C.mustnt be D.could be 3.You might just as well tell the manufacturer that male customers_ not like the design of the furniture.A.must B.shall C.may D.need 4.Children under 12 years of age in that country_ be under adult supervision when in a public library.A.mus
44、t B.may C.can D.need 5.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 6.I _ pay Tom a visit,but Im not sure whether I will have time this Sunday.A.should B.might C.would D.could 7.-I dont mind telling you what
45、I know.-You _.Im not asking you for it.A.mustnt B.may not C.cant D.neednt 8.-Excuse me,but I want 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 9.-Excuse me.Is that the right way to the Summer Palace?-Sorry,Im not sur
46、e,but it _ be.A.might B.will C.must D.can 10.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 11.You _ be tired-youve only been working for an hour.A.must not B.wont C.cant D.may not 12.-Who is the girl standing over there?-Well,if you _ know
47、,her name is Mabel.A.may B.can C.must D.shall13.There_ be any difficulty in passing the road test since you have practised a lot in the driving school.A.mustnt B.shant C.shouldnt D.neednt 14.-Lucy doesnt mind lending you her dictionary.-She _.Ive already borrowed one.A.cant B.mustnt C.neednt D.shoul
48、dnt15.He _ have completed his work;otherwise,he wouldnt be enjoying himself by the seaside.A.should B.must C.wouldnt D.cant 16.I _ have been more than six years old when the accident happened.A.shouldnt B.couldnt C.mustnt D.neednt 17.This cake is very sweet.You _ a lot of sugar in it.A.should put B.
49、could have put C.might put D.must have put 18.He paid for a seat,when he _ have entered free.A.could B.would C.must D.need 19.I was on the highway when his car went past followed by a police car.They _ at least 150 kilometers an hour.A.should have been doing B.must have been C.could have done D.woul
50、d have done 20.-Tom is never late for work.Why is he absent today?-Something _ to him.A.must happen B.should have happened C.could have happened D.must have happened 21.-Do you know where David is?I couldnt find him anywhere.-Well.He _ have gone far-his coat is still here.A.shouldnt B.mustnt C.cant
