1、中考语法专题情态动词壹课堂导入You mustnt swim here.You mustnt smoke here.You can park your car here.贰知识梳理概念 情态动词是用来表示说话人的语气或情态，包括请求、命令、允诺、可能、需要、愿望、义务、能力等。用法 1.情态动词有自己的词义，但不能单独做谓语，只能加动词原形一起构成谓语 2.情态动词没有人称和数的变化（一）can和could1.表示能力，指有能力做某事，意为“能够”I can speak fluent English now,but I couldnt last year.我现在能够说一口流利的英语，但是去年我
2、不能。2.表示请求和允许。表示请求，口语中常用could代替can，使语气更委婉；意为“可否、可以”Can we turn the air conditioner on?我们能把空调打开吗?Could you please tell me where he has gone?你能不能告诉我他去了哪?3.用在否定、疑问或感叹句中，意为“可能”Its dark in his house.He cant be at home.他家一片黑，他不可能在家的。4.表示推测，用在否定句、疑问句和感叹句中，表示惊异、怀疑、不相信等态度，意为“可能，能够”How can you be so crazy?你怎么能
3、够如此疯狂?5.could 用来表示请求时，语气委婉，主要用于疑问句，不能用于肯定句，答语应用can -Could I use your dictionary?-Yes,you can./No,Im afraid not.6.can和be abele to的辨析1）can（could）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，而be able to 则有更多的形式。2）表示在过去某时的某一场合经过一番努力，终于做成了某事，或者表示“有能力克服困难做成某事”通常不用could，而用 was/were able to来表示。这时，was/were able
4、 to相当于managed to do或 succeed in doing.After the accident it was a long time before she was able to walk again.车祸后过了很长时间她才能再次走路。The army were able to defeat their enemy.军队成功抵御了他们的敌人。（二）must1.用于第一人称表示说话人有义务，有必要做某事；用于第二、三人称表示命令或要求某人做某事。You must come to school on time.你必须准时到校。We mustnt waste any more ti
5、me.我们不准再浪费了。2.回答带有must的问句时，否定回答常用neednt或dont have to，表示“不必”，而不用 mustnt。-Must I come back before ten?-Yes,you must.(No,you neednt)3.表推断、预期或人以避免，意为“肯定是、必然会”。You must be hungry after a walk.走了一路你肯定饿了。4.must和have to的辨析1）意义相近，但must表示的是说话人的主观看法，而have to 则往往强调客观需要。The film is not interesting.I really must
6、go now.I have to go now,because my mother is in hospital.2）must只有一种形式，而 have to 则涉及各种人称、时态等方面的变化形式。I had to work hard when I was your age.3）两者的否定意义不同，mustnt表示禁止，不许，dont have to表示不必。You mustnt go there.You dont have to go there.（三）shall1.表示允许用于第一、二、三人称构成的疑问句，表示征求对方意见或请求指示，表示“商量酌”Shall I open the wind
7、ow?Shall we say 6 oclock,then?What shall I get for dinner?2.用于第二、三人称陈述句中，表示说话人给对方的命令、警告、允诺或威胁。Dont worry，you shall get the answer this afternoon.（允诺）He shall be sorry for it one day，I tell you.（警告）You shall do as I say.（命令）If you children dont do as I tell you，you shall not go to the party.（威胁）（四）sh
8、ould和ought to1.should和ought to 意思相同，意为“应该”，否定形式为 shouldnt、oughtnt to 2.表示劝告、建议，也能表示义乌，指应该做，且有一种道义上的责任 What should I do Should I trust him?You should read his new book.I should help him because he is in trouble.（五）will和would 1.用于表示意志、愿望和决心。will指现在，would指过去。They said they would meet us at 10:30 at the
9、 station.I will never do that again.2.表示请求、建议等，用would比用will委婉、客气。Will you please take a message for him?Would you please tell me yourtelephone number?（六）need和dare1.表示“需要，必要”之意，做情态动词时用法即情态动词的基本用法，need do，否定形式为neednt do，一般疑问句把need提前即可。Need we leave soon?Yes,you must.(No,you neednt)2.做实义动词时，其变化与一般的实义动词
10、相同，后接带 to 的不定式（need doing=need to be done），过去式用 needed、did you need和 didnt need，肯定式用 needs/needed/need，疑问式用 do、does、did 提问，否定式要在前面加 dont、doesnt、didnt He needs to see a doctor.They didnt need to start so early.3.dare 用于表示“敢于”之意，既可以做情态动词，也能做实义动词，用法与need相同。（一）表示请求1.can、could和may都能表示请求，意为“可以，能够”-May I b
11、orrow your pen?-Yes,you can.2.could可以用于现在时的句子中，仅表示语气的委婉，而不表示时态 -Could I park my car here?-Yes,you can.在宾语从句中要注意从句时态：Could you tell who is talking to my mum over there?（二）表示猜测1.must用于肯定句中表示猜测，意为“肯定是”，否定句和疑问句中需改为can或cant，大多情况下是根据现有情况进行推测，有一定依据 Listen to his voice.He must be a famous singer.The door is
12、 closed.She cant be at home.2.may 和might表示猜测时意为“可能”，might的可能性较低 It may rain this afternoon.She might come to join us tomorrow.叁典型例题1.-Is that man Mr.Green?-It _ be him.He has gone to Paris on business.A.may B.must C.cant D.shouldnt2.-Whats wrong with Judy?She has been absent for two days.-Oh,she _ b
13、e ill.Lets go to ask Mr.Green.A.may B.need C.would D.should1.【解析】答案C 选项意思may可能；must一定，必须；cant不可能；shouldnt不应该。根据He has gone to Paris on business，可知他出差去巴黎了，所以那个人不可能是Green先生，cant不可能，故选C。2.【解析】答案A 选项意思may可能；need需要；would将会。根据She has been absent for two days。可知这里说她缺席了两天了，可以推断她可能病了。may可能；故选A。3.-Must I clea
14、n the room now?-No,you _.You can do it later.A.neednt B.cant C.may not D.shouldnt4.-Mum,_ I play football this afternoon?-Sure,but you _ finish your homework first.A.may;could B.can;must C.can;mustnt D.may;cant3.【解析】答案A 根据No和You can do it later。可知下面为否定回答，must的含义是必须一定，其否定形式mustnt表示禁止的含义。在这里不是禁止的意思。mu
15、st的否定回答一般可借助于neednt和dont haveto来构成，表示不必。故选A。4.【解析】答案B 根据 I play football this afternoon，可知这里表示一种请求，这里用can表示能；再根据but you.finish your homework first，可知这里必须先完成作业，语气较为强烈，所以在这里用must表示一定要做的事。故选B。5.-Many people play with mobile phones all day instead of reading books.-Thats too bad.Everyone _ be a book lov
16、er.Reading is more enjoyable.A.may B.should C.would D.must6.-You look very pretty,if I _ say so.-Thanks a lot for saying that.A.must B.may C.will D.have to5.【解析】答案B may，可能，也许should表义务，意为“应该”（某件事宜于做），用于各种人称would将要，一种更委婉的说法must 表示“必须”，语气较强烈。根据Everyone _ be a book lover，可知这里是说每个人都应该是一个爱书者，表示某件事宜于做，所以这里
17、用should。故选B。6.【解析】答案B must 一定，必须；may可以；will将要；have to不得不。根据You look very pretty，if I _ say so。可知这里的意思是你看起来很漂亮，如果我可以这么说，在这里may表示可以，故选B。7.-CanI goswimming,Mom?-Certainly.But you _ be back by four.A.can B.may C.might D.must8.-Lets go climbing,shall we?-You _be joking!Dont you know Im afraid of high pla
18、ces.A.must B.can C.may D.should 7.【解析】答案D can能够，可能may可以might可能must一定，必须，can 可表示“可以，能够”，即表示允许或者能力，也可表推测。常常用于否定推测。may 也可表示“可以”的意思，表征求意见或允许might比may表达更委婉一些。根据But you _ be back by four,可知这里表示四点之前必须回来，是要求，must一定，必须。故选D。8.【解析】答案A can可以，能够，should应该，may可能，must必须，一定。也表示肯定的推测。根据Dont you know Im afraid of high
19、 places，可知我恐高，所以你一定是在开玩笑。must必须，一定。故选A9.Please dont make so much noise.I _ hear the speaker very well.A.neednt B.mustnt C.cant D.shouldnt10.All the students _ know cheating in the exam is not allowed.A.need B.may C.must D.can9.【解析】答案 C Neednt不必,mustnt不可以,cant不能,shouldnt不应该。根据I _ hear the speaker ver
20、y well.可知这里的意思是不能很好的听清演讲者的话了。cant不能。故选C。10.【解析】答案 C need需要；may可以；must一定，必须；can可能。根据All the students _ know cheating in the exam is not allowed.可知所有的学生都必须知道在考试中作弊是不允许的，这是法律明文规定的，都必须遵守的，must一定，必须。故选C。肆课堂练习一.用can，may，must，need，have to，had better的适当形式填空。1.You _ return the library book on time.2.I _(not)
21、find the way to the hospital._ you show me the way?3._ I finish the work right now?No,you _(not).You _ do it later.4.He said he _(not)come tonight.5.Her mother was ill.She _ stay at home and look after her.6.Its time for class.You _ stop playing football or you _ be late for class.7.We _ start right
22、 now,or they would get there first.8.The cloud is lifting,so it _(not)be a rainy day tomorrow.二.选择填空。1.Excuse me.Will you please tell me the way to the railway station?Oh,sorry,but I dont know.You _ go and ask that policeman.A.may B.must C.would D.should 2.John _ come to see us tonight,but he isnt v
23、ery sure yet.A.may B.can C.has to D.must3.This book _ Lucys.Look!Her name is on the books cover.A.cant be B.may be C.mustntbe D.mustbe4.-_ I finish the work today?-No,you _ A.Must,cant B.Must,neednt C.May,neednt D.Can,mustnt 5.-_ we ask you some questions?-Sure,go ahead!A.Will B.Shall C.Must D.Need
24、6.-Youmust come back every month.-Yes,I _.A.must B.should C.will D.can7.Where is Tom?He hasnt come to school today.I think he _ be ill.A.has to B.had better C.can D.must8.Whats the time now?Its still early.You _ worry about the time.A.may not B.dont haveto C.cant D.dont need9.I visit Lucy on Sunday,
25、Mum?Yes,you _.A.Must,can B.May,may C.Need,need D.May,need10.Computers _ process difficult problems very quickly.A.can B.must C.should D.need11.-Must we clean the room right now?-No,you_.You _ clean it after lunch.A.neednt;may B.neednt;must C.Mustnt;can D.mustnt;may 12.John _ come to see us tonight,b
26、ut he isnt very sure yet.A.may B.can C.has to D.must13.Children _ play with fire.A.mustnt B.cant C.shouldnt D.neednt14.-_ I come in,Mr.Green?-Yes,come in,please.A.Must B.Need C.Will D.May15.-Must I finish the work today?-No,you _.You _ finish it tomorrow.A.mustnt;may B.cant;can C.neednt;may D.neednt
27、;must 16.She _ know the answer,but Im not sure.A.maybe B.may be C.may D.must17.-Look at the sign!-Oh,I see.We _ waste water.A.can B.must C.mustnt D.neednt18.-Must we leave now?-No,we _.We still have two more hours.A.cant B.mustnt C.neednt D.shouldnt19.-Can you ride a horse?-No,I _.A.neednt B.may not
28、 C.cant D.mustnt20.-Miss Li,must we hand in our homework right now?-No,you _.You can hand it in tomorrow.A.dont B.mustnt C.neednt D.may not 21.You _ eat the soup if you dont like it.A.shouldnt B.mustnt C.neednt D.cant22._ you wait a few more minutes?Itll be your turn soon.A.Must B.Should C.Could D.M
29、ight23.She _ be here.I saw her come in.A.can B.may C.should D.must24.I cant go to the cinema with you because I _ stay here until my mother comes back.A.can B.could C.may D.must 25.-Hey,Ted!You _ never play in the street.Its not safe.-Sorry,Mum.I wont again.A.need B.must C.can D.may【参考答案】.1.must 2.c
30、ant,Could 3.Must,neednt,may 4.couldnt 5.had to 6.must,may 7.had better 8.cant二.15AADBB 610CDBBA 1620CCCC 1115 AAADC 2125 CCDDB0伍课后检测单项选择。1.Michael _ be a policeman,for hes much too short.A.neednt B.cant C.shouldnt D.may2.-Will you stay for lunch?-Sorry._.My brother is coming to see me.A.I mustnt B.c
31、ant C.I neednt D.I wont3.Peter _ come with us,but he isnt very sure yet.A.must B.may C.can D.will4.-Ann,_ I have some more cake?-Certainly,help yourself.A.need B.must C.will D.may5.The house is dark and quiet,so the Browns _ have gone to bed.A.must B.should C.ought D.would6.-Must we do it now?-No,yo
32、u _.A.neednt B.mustnt C.wont D.shouldnt 7.Johnny,you _ play with the knife,you hurt_ yourself.A.wont;cant B.mustnt;may C.shouldnt;must D.cant;shouldnt8.-_ I use your eraser,Rose?-Sure.Here you are.A.May B.Would C.Need D.Must9.-Can I borrow your dictionary?-Yes,you _.A.can B.must C.should D.need10.-M
33、ust I hand in my exercise book now,Mr.Zhao?-No,you _.You may give it to me tomorrow.A.neednt B.mustnt C.cant D.shouldnt 11.-Congratulations!Youve got the first prize in the English Contest.-_ it be true?Its unbelievable!A.May B.Should C.Must D.Can12.You _ finish the report today.Any time before Frid
34、ay is OK.A.mustnt B must C.need D.neednt 13.-Could I use your eraser for a while?-Yes,of course you _.A.could B.can C.will D.should14.-Can you come to my party on Wednesday?-Sorry,I cant.I _ finish my homework.A.may B.would C.have to D.should15.-_ I watch TV now,Mom?-No.Its too late,and you _ go to
35、bed.A.May;have to B.Will;should C.Can;will D.Must;need16.-Must I finish my homework today,Ms Liu?-No,_.A.you mustnt B.you dont have to C.you cant D.you shouldnt17.According to the new traffic laws,people _ driver after drinking wine or beer.A.wouldnt B.couldnt C.neednt D.mustnt18.-Can I wear any clo
36、thes I like to school?-No,you cant.You _ wear a uniform（校服）.A.might B.will C.must D.would 19.-Will you stay for some more days?-Sorry,I _.My mother called to ask me to go back at once.A.mustnt B.may not C.cant D.wouldnt 20.-May I take the magazine out of the reading room?-No,you cant.You _ read it h
37、ere.Its the rule.A.must B.would C.may D.might21.-Must I get up early tomorrow morning?-No,_ A.you mustnt B.I dont think you have to C.you cant D.you need22.-Whos singing in the next room?be her.She has gone to New York.-It _.A.cant B.must C.shouldnt D.can【参考答案】15 BBBDA 610 ABAAA 1115DDBCA 1620 BDCCA 2122BA谢 谢
