1、He be Curnane!He be thinking.He be a common boy.mustmightcant1ppt课件表推测的三种句式表推测的三种句式The light is on,so somebody _ be at home.mustThe light is on,so my sister _ be at home.may/might 1.在肯定句中一般用在肯定句中一般用must,may/might，语气语气逐渐逐渐减弱。减弱。2ppt课件常用于表推测的情态动词常用于表推测的情态动词will wouldought toshould（一定）（一定）（可能）（可能）（很有可能
2、）（很有可能）（很有可能）（很有可能）（应该，很有可能）（应该，很有可能）（应该，很有可能）（应该，很有可能）（可能）（可能）（可能）（可能）（可能）（可能）肯定肯定推推测测最最 强强最最 弱弱mustmightcancouldmay3ppt课件Its sunny.It _ rain.cant表推测的三种句式表推测的三种句式 2.在否定句中用在否定句中用cant/couldnt(不可能不可能)，may not/might not(可能不可能不)。He _ know how to answer this question./might notmay not4ppt课件常用于表推测的情态动词常用于
3、表推测的情态动词（禁止禁止,不许不许）（可能）（可能）（肯定不肯定不,不可能不可能）（肯定不肯定不,不不可能）可能）（可能（可能不不）否否定定推推测测最最 强强最最 弱弱must notmight notcantcouldntmay not（不用于推测不用于推测）5ppt课件表推测的三种句式表推测的三种句式 3.在在疑问句中，一般只使用疑问句中，一般只使用can/could。she have finished her homework?your sister be at home now?CouldCan【口诀口诀】can不肯，may/could/might不问，must不否问注：注：can表
4、示推测时，不用于表示推测时，不用于肯定句；肯定句；may/might/could表示推表示推测时，不用于疑问句；测时，不用于疑问句；must表示推测时，不用表示推测时，不用于否定句或疑问句。于否定句或疑问句。6ppt课件He _ to music.对现在或一般情况的推测“情态动词+be”“情态动词+be doing”“情态动词+动词原形”must be listing He _ at home now.The light isnt on.cant beHe _ in his office.may work7ppt课件She _ very happy when she opens the doo
5、r.对将来推测，对将来推测，“情态动词情态动词+动词原形动词原形”must be8ppt课件The ground is wet.It _ yesterday night.对对过去或已经完成的推测过去或已经完成的推测，“情态动词情态动词+have+过去分词过去分词”may have rained9ppt课件表对已经发生的事情的推测，意为“一定，想必”，在句子中表示的是一种肯定的推测。这种结构一般只用于肯定句。1.must have done否定形式：否定形式：cant(couldnt)have doneThey out,because the light is still on.He didnt
6、 hear the phone.He asleep.“不可能，肯定不会不可能，肯定不会”must have beencant have gone10ppt课件表表对过去的时间里可能发生的事情的推测，对过去的时间里可能发生的事情的推测，一般只用于否定句和疑问句一般只用于否定句和疑问句。2.can/could have doneHe cant have finished the work so soon.用于用于肯定句中，常用来表示本来可以完成而肯定句中，常用来表示本来可以完成而实际未完成的动作实际未完成的动作。We could have walked to the station,it was
7、so near.“本来能做本来能做.(而实际上没做而实际上没做)”11ppt课件1)表对已经发生的事情不太肯定的推测，意为“可能已经，或许已经”3.may/might have done2)虚拟用法：表可以做，但却没有做。If we had taken the other road,we might have arrived earlier.He might have given you more help,but he was very busy.12ppt课件三三种句式种句式常用于表推测的情态动词常用于表推测的情态动词情态动词情态动词表表推测的三种时态推测的三种时态几组几组对过去对过去的的
8、推测推测can/could have donemust have donemay/might have done13ppt课件Exercise:1.Whose earrings are these?They _ be Marys.She wears earrings sometimes.2.Carls _ come to the party tonight,but Im not sure.3.The telephone is ringing,but nobody answer it,he _ be at home.4.-Is this Lan Qiangs boxing glove?-Yes,
9、it _ be his.This is his name on the back.5.Youd better take an umbrella.It _ rain this afternoon.may/could/might must may/might/could cant may/might/could 14ppt课件6.Its the library!So you _ know shouting is not allowed here.7.-Have you decided where to spend your summer holiday?-Not yet.We _ go to Qingdao.8.-Is Jessica giving us a speech this evening?-No,it _ be her.She has gone to Japan.9.-What will the weather be like tomorrow?-It _ be rainy,cloudy,or sunny.Who know?10.You _ be tired after playing sports for a long time without a rest.mustmaycantmightmust15ppt课件
