英语人教版八年级下册情态动词could的用法

GrammarFocus情态动词——couldIfweneedhelp,whatshouldwesaypolitely?Whichisthemostpoliteone?1.Sweepthefloor,Peter!2.Canyousweepthefloor,Peter?3.Couldyoupleasesweepthefloor，Peter?Couldyoupleasecleanyourroom?Yes,sure.Couldyoupleasedothedishes?Sorry,Ican’t.Ihavetodomyhomework.CouldIgotothemovies?Yes,youcan.CouldIusethecar?No,youcan’t.Ihavetogoout.1.could表示请求，语气委婉，显得有礼貌Couldyoupleasecleanyourroom?你可以打扫你的房间吗？肯定回答：Yes,Ican.Yes,sure./Yes,ofcourse.是的，我可以。否定回答：Sorry,Ican’t.Ihavetodomyhomework.对不起，我不得不做作业。2.could表示请求许可，希望得到允许。CouldIgotothemovies?我能去看电影吗？肯定回答：Yes,youcan.Yes,sure.当然可以。否定回答：No,youcan't.不，不行。在表示请求帮助或请求允许的疑问句中，我们常用could代替can，以表示礼貌、委婉或不确定的语气，而can则不具有这些语气。这样用时，不能把could看作为can的过去式形式。3.could与can的区别could与can都是情态动词，could是can的过去式。二者都可用于表示请求，但是用法稍有不同。can表示一般性的请求，语气随便，常用于熟人之间或长辈对晚辈、上级对下级的场合；Canyoutellusyourstory,Tony?你能给我们讲讲你的故事吗，Tony？could表示有礼貌的请求，语气委婉，常用于非熟人之间或晚辈对长辈、下级对上级的场合。—CouldyoutellusifitsnowsinwinterinAustralia?请告诉我们，澳大利亚冬天下雪吗？—Sure.当然可以。—Couldyoupleasedosth?No,Ican’t…Ihaveto…“No”Sorry,Ican’t…Ihaveto…Yes,Ican.Allright.“Yes”Sure.Noproblem.Certainly.Couldyouplease…?sweepthefloorfoldyourclothescookthemealcleanthewindow小试牛刀()1.—Excuseme,couldyouhelpmewiththeheavybox?—__________.A.Yes,IdoB.Itdoesn’tmatterC.Ofcourse小试牛刀()2.—CouldIhaveyourname,please?—_____________.A.Sorry,I’mnotB.Yes,youcouldC.YoucancallmeJenny小试牛刀()3.Couldyouplease________melookformydog?A.helpB.helpedC.tohelp()4.—CouldIuseyourbike?—Sure,you_________.A.mightB.canC.shouldCould的用法1.IcouldrunfastwhenIwasachild.2.Couldyouhelpme?3.Youcouldtalktoyourteachernow.4.Hecouldn’tbeattheschoolthen.can的过去式礼貌的请求提出建议推测HomeworkCouldyoupleasewritedown5sentenceshowtoaskorsuggest?