情态动词can, may, must的用法

情态动词can,may,must的用法,情态动词后接动词原形;没有人称和数的变化;不能单独作谓语,与后面的动词共同作谓语;其否定形式在后面直接加not。,Modalverbs情态动词,can/cannotmay/maynotmust/mustnot,Modalverbs情态动词,can/cannot,1.表示能力(会)MarycanspeakEnglish,butshecannotspeakFrench.2.表示允许(可以)CanIuseyourdictionary?Icantfindmine.3.表示推测(可能)-通常用于否定形式Hecantbeintheoffice.Isawhimgooutjustnow.,1.S1_Kitty_?S2_.,2.S1_Kitty_?S2_.,Canspell,Yes,shecan,Canadd,No,shecant,3.S1_Derek_?S2_.,4.S1_Kitty_?S2_.,Cansubtract,Yes,hecan,Canmultiply,No,shecant,may/maynot,1.表示允许(可以)MayIcomein?2.表示推测(可能)-通常用于肯定形式Shemaybestillwaitingforus.3.表示祝愿Mayyouhaveahappyweekend.,may的用法:,may/maynot,以may开头的疑问句，其否定回答用cant或mustnt。-MayIgohomenow?-Yes,youmay.No,youcant.,maynot的用法:,Answers:,1.MayIcarryyourbagforyou?2.MayIopenthedoor?3.MayIgetyouachair?4.MayIswitchontheTV?5.MayIborrowyournewbicycle?,must/mustnot,1.must表示必须Youmustdoyourhomeworkfirst.2.must表示一定(肯定性推测)Hemustbeathome.,must的用法:,must/mustnot,1.mustnt表示禁止(不准；不允许)Youmustntsmokehere.2.以must开头的疑问句，其否定回答要用neednt.-MustIcleantheclassroomnow?-Yes,youmust.No,youneednt.,mustnot的用法:,Whatdothesignsmean?Doyouknow?,Youmustnotcycle.,Youmustbecareful.,Youmustturnleft.,Youmustnotenter.,Youmustpaytenyuan.,Youmustkeepsilent.,Youmustnotturnright.,Youmustnotsmoke.,.用适当的情态动词填空：。1.Icanplayfootball._youswim?2.Dontworry.You_returnmethisbooktomorrow.3.Mygrandmaisill.You_talksoloudlyhere.4.Icantplaywithyou.I_finishmyhomeworkfirst.5.I_getupearlytomorrow.becauseIhaveameeting.6._youpleaseopenthewindow?,Can,may,cant,must,must,Can,9.Nobody_livewithoutair.10._hespeakChinese?Yes,alittle.11.Thebook_bereturnedbeforeSaturday.12._Icomein?Yes,please.13.You_giveupsmokingatonce.Itsbadforyourhealth.14.Excuseme._Iaskyouaquestion?15._youtellmewherethestationis?16._Ifinishtheworknow?No,you_.You_doitthisevening.17.MayIuseyourdictionary?Sorry,you_.Iamusingitnow.18.Lookatthegrou