情态动词完成时的推测.ppt

,Whyistheroadsowet?,Itmusthaverainedlastnight.,A:Wherearethegirls?Cantheyhavegonehome?B:No,theycanthavegonehome.Itssoearly.,-Look,thelightsareoffintheirroom.-Wherehavetheygone?-Theymighthavegonetothecinema.,A:Hereisadollforyourdaughter.B:Thankyousomuch.Itsbeautiful.Butyouneednthaveboughtit.Shehassomanyathome.,Findingtherule,Believingwhathappenedinthepastisthecase(usedonlyinpositivesentences),indicatingthatsomethingwasapossibilityinthepast,thoughitdidnotactuallyhappen(negativeorinterrogativesentences),Suggestingthatitispossiblethatsomethinghappenedorwastrue(usedonlyinpositive/negativesentences),indicatingthatsomethingdidnot/didhappen,butthespeakerwishesithad(not)happened.,indicatingthatitisnotnecessaryforsb.todosth,thoughhe/shedidit.,musthavedone对过去的非常肯定的推测（语气最强）,对已发生的过去情况的推测，若陈述句谓语部分有“musthavedone”，而且有表示过去的时间状语,问句部分用didnt；,1)Theymusthavegonetherelastnight,didntthey?,2)Theymusthavearrivedbynow,haventthey?,对已发生的过去情况的推测，若陈述句谓语部分有“musthavedone”，若没有表示过去的时间状语，问句部分用havent或hasnt.,3)HemusthavebeentotheGreatWall,hasnthe?,对已发生的过去情况的推测，若陈述句谓语部分有“musthavedone”，若没有表示过去的时间状语，问句部分用havent或hasnt.,这个房间昨天肯定被清扫了。Theroom_yesterday.,musthavebeencleaned,他一定已经背了5000单词了。He_5,000words.,musthavelearnt,Youmusthaveseenthefilm“JourneytotheWest”,_?,haventyou,TheymusthavebeentotheWorldExpolastweek,_?,didntthey,canhavedone对过去的疑问推测,canthavedone对过去的否定推测,疑问句和否定句,-WhereisJohn?Canhehavegonetotheplayground?-No,hecanthavegonetotheplaygroundItisraining.,-_MrKing_theletter?金先生已经收到那封信了吗？-No,he_it.不，他不可能收到。,Can,havereceived,canthavereceived,may/mighthavedone某事有可能发生过(表示对过去的不太肯定的推测，语气比musthavedone弱),用于肯定句和否定句(may的语气比might稍强),-WheredidAdamgetthatnewfootball?Hehasntgotanymoney.-It_apresent.Afterall,itwashisbirthdaylastweek.A.mighthavebeenB.mightbe,He_outbecausethelightwason.A.maynothavegoneB.mayhavenotgoneC.maynotgoD.mustnothavegone,neednthavedone本没有必要做某事（但此事已做）,We_theplantbecauseitrainedlastnight.(本无必要),neednthavewatered,shouldnthavedone本不该做某事（但此事已做）,表示责备,Heshouldhaverepairedthebikeyesterday.,shouldhavedone本应该做某事（但此事未做）,表示责备,Oh,Imnotfeelingwellinthestomach.Ishouldnthaveeatensomuchfriedchickenjustnow.,你本应该先完成你的作业。You_yourhomeworkfirst.,shouldhavefinished,你本不应该跟我撒谎。You_tome.,shouldnthavelied,高考例析,1.SorryImlate.I_haveturnedoffthealarmclockandgonebacktosleepagain.（2000北京春季）A.mightB.shouldC.canD.will,答案为A。表推测的用法。句意：对不起,我迟到了。我(当时)兴许是关了闹钟又回去睡觉了。might相当于may,但语气更加不肯定。,2.Iwasreallyanxiousaboutyou.You_homewithoutaword.(01全国)A.mustntleaveB.shouldnthaveleftC.couldnthaveleftD.needntleave,答案为B。虚拟语气用法。句意：我（那时）真地很担心你。你本不应该不留个话就离开家。,3.IlltellMaryabouthernewjobtomorrow.You_herlastweek.（04福建）A.oughttotellB.wouldhavetoldC.musttellD.shouldhavetold,答案为D。虚拟语气用法。句意：-我明天要告诉她我的新工作的情况。-你本应该上周告诉她。,4.Tomgraduatedfromcollegeataveryyoungage.Oh,he_havebeenaverysmartboythen.（04全国IV）A.couldB.shouldC.mightD.must,答案为D。表推测的用法。句意：汤姆很年轻的时候就大学毕业了。哦，他肯定是一个很聪明的男孩儿。,5.He_havecompletedhiswork;otherwise,hewouldntbeenjoyinghimselfbytheseaside.(05北京卷)A.shouldB.mustC.wouldntD.cant,答案为B。用法同4题。句意：他肯定做完了工作，不然他就不会在海边痛快地玩儿了。,6.DoyouknowwhereDavidis?Icouldntfindhimanywhere.Well.He_havegonefarhiscoatsstillhere.（05湖北卷）AshouldntBmustntCcantDwouldnt,答案为C。表推测的用法。句意：你知道大卫在哪儿吗？我哪儿也找不到他。瞧，他不可能走远他的上衣还在这儿呢。cant相当与couldnt，但后者语气更加委婉。,练习,ThewomanbiologiststayedinAfricastudyingwildanimalsfor13yearsbeforeshereturned.Oh,dear!She_alotofdifficulties!(05江苏卷)A.maygothroughB.mightgothroughC.oughttohavegonethroughD.musthavegonethrough,2.Ihavelostoneofmygloves.I_itsomewhere.（05北京春季）A.mustdropB.musthavedroppedC.mustbedroppingD.musthavebeendropped,3.Mr.White_at8:30forthemeeting,buthedidntshowup.（04广西）A.shouldhavearrivedB.shouldarriveC.shouldhavehadarrivedD.shouldbearriving4.Hepaidforaseat,whenhe_haveenteredfree.（05山东卷）A.couldB.wouldC.mustD.need,5.Tomisneverlateforwork.Whyisheabsenttoday?Something_tohim.(05江西卷)A.musthap