1、Lead-in ClassI play basketball well.you?No,I.ButI swim fast.Self-learn自学Yes,you.I sit down?_I come in?Yes,you No,you /_I get you a chair?Yes,thanksMayI sing beautiful songs.you?No,I.ButI play konfu.you?No,I.情态动词情态动词can,may和和must我们用我们用can表示表示“能力能力”，意思是，意思是“能、能、会会”，其否定式为，其否定式为cant。may/can表示表示“允许；许可允许；
2、许可”，意思是，意思是“可以可以”，其，其否定式为否定式为may not/cant。must表示表示“必必须须”，其否定式，其否定式mustnt表示表示“禁止禁止”。情态动词（modal verbs)：表示说话人的语气或情态，如请求、命令、愿望、能力以及可能性等。英语的情态动词有：can/could may/might must ought to shall/should will/would dare/dared need have to 能够可能必须应该应该意愿敢需要不得不+动词原形Probe I 探究一A can and cannotWe use and to say we are ab
3、le or not able to do things.We use electricity to do many things.We electricity.you think of an example?Yes,I./No,I.can/could能，能够，会，可以We can speak Chinese.He can draw pictures.许可You can(=may)go home now.表怀疑，难以置信He couldnt(cant)be her father,For hes too young.注意：could为can的过去式外，could还有表示语气婉转之义。Could I
4、 come in?比Can I come in?更有礼貌。但答语还用Yes,you can.No,you cant.Practice I 应用一1.Hi _ play football.2.Lo _ paint pictures.3.Hi _ speak as many languages as Lo.4.Both Hi and Lo_ dance.5.Lo _ drive a car,but he _play chess.6.Hi _ swim,but he _ play the guitar.Probe II 探究二B may and may notWe use and to ask fo
5、r and Give permission(许可）.We also use and for the same purpose.I use you mobile phone?Yes,you.No,you may/might允许；请求May I have a glass of water?May you borrow me your pen?可能；也许(may比might语气强）They may be in the library now.He might be at home.表示祝愿May you always be young.Practice II 应用二注意：might为may的过去式外
6、，might还有表示语气婉转之义。Might I have a look?比May I have a look?更有礼貌。但答语还用Yes,you may.No,you may not.Im going out._ I borrow your new bicycle?Yes,you may.Before you go to meet your friends,can you come and see the doctor with me?Yes,I_._I carry your bag for you?Yes,thats very kind of you,Benny.I m ready to
7、go._you open the door for me?Yes,I canThanksWe save water.We not waste water.You smoke.Must you do homework now?Yes,I must.Must you do your homework?No,I neednt.Can you play with me?Sorry,I cant.You may/can play with Jim.【试一试试一试】根据题意，选择合适的词语填根据题意，选择合适的词语填空。空。A)can,may,cant,may not1.Camels _ live in
8、hot areas.2.You _ pass the exam if you dont work hard.3._ I watch TV now?No,you _.B)must,mustnt4.You _ wear a thick coat when it is cold.5.You _ park your car here.Its against the rule.cancantMay/Canmay not/cant mustmustntProbe III 探究三C must and must notWe use and to tell people what to do or what n
9、ot to do.You do that Benny!We always be careful with electricity.They play near the heater.注意：must的提问肯定回答用must,否定用 neednt-Must I return the book?-Yes,you must.-No,you neednt.must必须；应该We must work harder.Must not意为不应该；不许；We must not be afraid of difficulties.You mustnt smoke here.Practice III 应用三drin
10、k more water go to bed earlyeat cold food share cups with othersgo out alone take the medicine on time1.I must drink more water.2._3._4.I must not_5._6._The doctor told what to do and what not to doI must go to bed early.I must take the medicine on time.eat cold food.I must not share cups with other
11、s.I must not go our alone.情态动词记忆口诀情态动词两要点;动词原形跟后面,说话语气较委婉,表能力 许可,责任或义务,否定回答neednt换;应该,愿,被迫,表客观.Sum up 小结 1.-_I download the article again?-No,you neednt.A.Shall B.Will C.Must D.Can2.-Must I stay at home,Mum?-No,you _.A.neednt.B.mustnt C.dont D.may not3.-May I go out to play basketball,Dad?-No,you _.
12、You must finish your homework first.A.mustnt B may not C.couldnt D.might not4.A computer _ think for itself.It must be told what to do.A.cant B.couldnt C.may not D.should5.-Could I borrow your dictionary?-Yes,you _.A.might B.must C.can D.should6.-_ the man there be our new teacher?-He _ be,but Im not sure.A.May,mustnt B.Can;mayC.Must;cant D.Can;cant 7.You _ be more careful next time.A.may B.must C.could D.might 8.Students _ smoke.A.cant B.mustnt C.might not BBB
