语法情态动词.ppt

,情态动词modalverbs,情态动词的基本用法特点1）情态动词除ought和have外，后面只能接不带to的不定式。2）情态动词没有人称，数的变化，即情态动词第三人称单数不加-s。,表示能力:can,could,beableto*beableto能用于各种时态。can/could只能表示现在或过去的能力。,1.表示能力、许可的情态动词的用法。,1.Acomputer_thinkforitself;itmustbetoldwhattodo.A.cantB.couldntC.maynotD.mightnot,2.Thefirespreadthroughthehotelveryquicklybuteveryone_getout.A.hadtoB.wouldC.couldD.wasableto,A,D,3.Theywill_runthismachineontheirowninthreemonths.A.canB.couldC.mayD.beableto,D,表示许可:may/might,can/could*might,could比较委婉,一般多用于疑问句.*can,may表达的语言比较随便.*在以could,might表示征询对方意见或表示请求时，回答应相应使用can,may.,5.CouldIborrowyourdictionary?Yes,ofcourseyou_.A.mightB.willC.canD.should6.MightIwatchTVaftersupper?Yes,you_.A.mayB.mustC.mightD.can,C,A,2.表示否定的情态动词的用法:,mustnt不准,禁止neednt没必要(=donthaveto)cant不能;不可能maynot不可以;可能不shouldnt不应该(=oughtnotto)wont/wouldnt不愿意,can/may/must/need问句的回答方式,疑问句式,肯定句式,否定答式,youmay.,mustnt/maynot.,youmust,neednt/donthaveto.,youmust.,neednt/donthaveto.,7.You_returnthebooknow.Youcankeepittillnextweekifyoulike.A.cantB.mustntC.needntD.maynot8.Johnny,you_playwiththeknife,you_hurtyourself.A.wont;cantB.mustnt;mayC.shouldnt;mustD.cant;shouldnt,C,B,9.-Willyoustayforlunch?-Sorry,_.Mybrotheriscomingtoseeme.A.ImustntB.IcantC.IneedntD.Iwont10.-MayIpickaflowerinthegarden?-_.A.No,youneedntB.Not,please.C.No,youmustntD.No,youwont,B,C,表示推测情态动词的重要用法.,肯定的推测可能的推测否定的推测疑问的推测,must,对现在对过去,情态动词,may,might,cant,couldnt,can,could,+bedoing+havedone,+V.+havedone+bedoing可以用not表示“可能不”,+V.+havedone+bedoing,+V.+havedone+bedoing,shouldhavedone只用于谈论过去情况，主要有两个用法：用于推测过去已经发生的情况。如：Heshouldhavearrivedbynow.此时他本该到了。Thelettershouldhavearrivedbynow.信现在该到了。用于指本该发生而实际上未发生的情况。如：Youshouldhavetoldmesobefore.你早就应该告诉我。Youshouldhavetoldmeyouwerecoming.你该事先告诉我你要来呀。,1.Thegroundisratherwet,soit_haverainedlastnight,didntit?2.Tom_havegonetoShanghai,butImstillnotsureaboutit.3.Thegroundisverydry,soit_haverainedlastnight.4.Someonemusthavebrokenintoourbedroom.Who_havedoneit?5.IreallyregrettedwastingthehourswhenI_havestudiedhard,butitwastoolate.,must,may,cant,could,should,shall和will的比较,1.Ifyou_followmyadvice,I_offeryousomehelp.2._youmeethimrightnowor_hewaitoutside,sir?,will,shall,Will,shall,11.He_bepunishedifhedisobeys.如果他不服从,就要受到惩罚.12.Wearenotgoingtoquarrelatallifyou_onlyletmespeak.只要你让我说话,我们根本就不会吵架.13.-Sir,_hegoorstay?-Lethimgo.A.willB.shallC.mightD.could,shall,will,B,need的用法：1.实义动词(有人称和数的变化）sth.sb.+needtodosth.sth.todosth.,eg.Ineedsomehelp.,eg.Ineedtosleep.,eg.needtimetodosth.,Heneedstimetodohomework.,sth.+needdoing(表被动含义)=sth.+needtobedoneeg.Thehouseneedscleaning.=Thehouseneedstobecleaned,2.情态动词（没有人称和数的变化）need用于句首构成一般疑问句或neednt才为情态动词。注意：need作为情态动词时，后面必须接动词原形。常用句式：Needsb.dosth?sb.needntdosth.eg.NeedIgo?Heneedntgohomebybus.,Exercises:()1.Heneeds_timewithhischild.A.spendsB.spendingC.tospendD.spend()2.Tom_somemoneytobuybooks.A.needtoborrowB.needstoborrowC.needsborrowD.needsborrowing()3.You_theretoday.A.needntgoingB.neednttogoCdontneedtogoD.dontneedgoing()4.Theflowersneeds_.A.watersB.towaterC.wateringD.watered,C,B,C,C,情态动词短语的使用:,wouldliketodowouldratherdohadbetterdo.,Exercises:1.-_Ihaveaticket,please?-Sorry,sir.Alltheticketsweresoldouttenminutesago.A.MayB.NeedC.MustD.Should2.Thebook_bePeters.Look!Hisnameisonthebookcover.A.cantB.mustntC.mustD.need3.Yourmanager_intheoffice.HehasgonetoParis.A.canbeB.mustbeC.mustntbeD.cantbe4.-_Itakesomephotosinthehall?-No,you_.A.Can,needntB.Must,mustntC.Could,wontD.May,mustnt5._youpassmeapen?Idliketowritedownthetelephonenumbers.A.MustB.NeedC.CouldD.Should,can,cant,must,should,may,need,neednt,1.Eventhetopstudentinourclass_workoutthisproblem,soit_betoodifficult.2.Lookatwhatyouvedone.You_bemorecareful.3.Computers_processdifficultproblemsvery,veryquickly.4.You_gotoschooltomorrowifyougotothehospitaltolookafteryourmother.5.-It_beMarywhoisintheclassro