1、He be Curnane!He be thinking.He be a common boy.mustmightcant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/might1.在肯定句中一般用must,may/might，语气逐渐减弱。常用于表推测的情态动词will wouldought toshould（一定）（可能）（很有可能）（很有可能）（应该，很有可能）（应该，很有可能）（可能）（可能）（可能）肯定推测最强最弱mustmightc
2、ancouldmayIts sunny.It _ rain.cant表推测的三种句式2.在否定句中用cant/couldnt(不可能)，may not/might not(可能不)。He _ know how to answer this question./might notmay not常用于表推测的情态动词（禁止,不许）（可能）（肯定不,不可能）（肯定不,不可能）（可能不）否定推测最强最弱must notmight notcantcouldntmay not（不用于推测）表推测的三种句式3.在疑问句中，一般只使用can/could。she have finished her homewo
3、rk?your sister be at home now?CouldCan【口诀】can不肯，may/could/might不问，must不否问注：can表示推测时，不用于肯定句；may/might/could表示推测时，不用于疑问句；must表示推测时，不用于否定句或疑问句。He_tomusic.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 homenow.The light isnt on.cant beHe _ in his office.may workShe_veryhappywhensh
4、eopens the door.对将来推测，“情态动词+动词原形”must beThe ground is wet.It _yesterday night.对过去或已经完成的推测，“情态动词+have+过去分词”may have rained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：cant(couldnt)have doneThey out,because the light is still on.He didnt hear the phone.He asleep.“不可能，肯定不会”m
5、ust have beencant have gone表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。2.can/could have doneHe cant have finished the work so soon.用于肯定句中，常用来表示本来可以完成而实际未完成的动作。We could have walked to the station,it was so near.“本来能做.(而实际上没做)”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
6、the other road,we might have arrived earlier.He might have given you more help,but he was very busy.三种句式常用于表推测的情态动词情态动词表推测的三种时态几组对过去的推测can/could have donemust have donemay/might have doneExercise:1.Whose earrings are these?They _be Marys.She wears earrings sometimes.2.Carls _ come to the party tonig
7、ht,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,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 6.Its the library!So yo
8、u _ 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.mustmaycantmightmust
