人教新课标必修三-情态动词PPT课件

.,1,Grammar,modalverbs,.,2,Firstwealthishealth.Q1:Whatshould/shouldntwedotokeephealthy?Q2:Whatkindoffoodmustweeattobestrong?Q3:Whatoughtwetoeattostayslim?,.,3,主要情态动词,can,couldmay,mightmust/havetoneeddarewill/wouldshall/should/oughtto,Whatmodalverbshaveyoulearned?,.,4,1.情态动词有一定的意义，只表示期待或估计某事的发生，不能表示正在发生或已经发生的事情。2.没有人称和数的变化，即情态动词第三人称单数不加-s。3.不能独立使用，它和后面的动词构成谓语。4.情态动词除ought和have外，后面只能接动词原形5.情态动词没有非谓语形式，即没有不定式，分词等形式。,只作情态动词的can/could,may/might,oughtto,must,可情态可实义的need,dare,可情态可助动词的shall/should,will/would,相当于情态动词的haveto,情态动词的语法特征,.,5,1.must&need&haveto,.,6,注意：1)must表示推测时，只能用于肯定句。,mustdo对一般时的肯定推测,musthavedone对过去发生的事情作出的肯定判断,mustbedoing对现在的动作进行肯定推测,e.g.他们买了一辆新车。他们一定很有钱。,Theyhaveboughtanewcar.Theymusthavealotofmoney.,他现在一定在看小说。,Hemustbereadingnovelsnow.,路是湿的。昨天晚上一定下雨了。,Theroadiswet.Itmusthaverainedlastnight.,.,7,-Needhestartfromthebeginning?-Yes,hemust.-No,heneednt/doesnthaveto.,1.作情态动词时,仅用于否定或疑问句,后接动词原形,表“需要”,2)need,Youneedntreturnthebooknow.,2.neednthavedone表示做了本不必要做的事情,意为“本不必要”,OurcolorTVsetisstillgoodenough.Youneednthaveboughtanewone.,3.作实义动词时,表示“需要”，有人称、时态、和数的变化,Heneedstofinishitthisevening.Theclassroomneedscleaning.,.,8,4)注意对need问句的回答:-NeedIfinishtheworktoday?-Yes,_.No,_.No,_.,youmust,youneednt,youdonthaveto,neednt对其它情态动词的回答:-ShallItellJohnaboutit?-No,you_.-No,you_.,-Mustwedoitnow?-No,you_.-No,you_.,neednt,donthaveto,neednt,donthaveto,.,9,1表示某人通过努力克服困难做成某事,要用was/wereableto.2could,might,would表委婉语气用于疑问句,答语仍须用can,may,will.3can用于肯定句中,可表示”有时可能”,2.can/could,4.can/couldhavedone“本可以，本可能做某事”用于肯定句中，表示对过去发生的事情做出的判断。,你本来可以考的更好。,Youcouldhavehadabettermark.,5.can/couldnothavedone对过去发生行为进行推测:不可能做某事,1)刚才我还看见他了，所以他不可能出国的。,Isawhimjustnowsohecouldnthavegoneabroad.,2)门是锁着的，所以她不可能在家。,Thedoorwaslocked，soshecouldnthavebeenathome.,.,11,3.may/might,注意：might/mayhavedone,表示对过去发生的动作进行可能性推测，,1）他可能去医务室了。,Hemayhavegonetotheclinic.,2）他可能已经从报纸上知道这个消息了。,Hemighthavereadaboutthenewsinthenewspaper.,.,13,1.-MayIuseyourpencil?-Yes,youmay./No,youmustnt.,2.Shemaynotbeworkingnow.3.Johnmightbeathomenow.4.Helenmaygoonthetripwithus,butsheisntverysureyet.,5.Shemay/mighthavereaditinthepaper.,6.Hemaynothavefinishedreadingthebook.,.,14,4.will/would,.,15,5.shall,should和oughtto,.,16,YoushalldoasIsay.(命令),1.在陈述句中,shall用于二、三人称表示允诺、警告、命令、决心等。,ShallIopenthewindowforyou？（征求意见）,2.在疑问句中,用于一、三人称，用来表示请求或征求意见。,注意：,Tellhimthatheshallhavethebooktomorrow.(允诺),Nothingshallstopmedoingit.(决心),Shallhefetchsomewaterforyou？（请求）,.,17,Youngpeopleshouldlearnhowtousecomputers.,3.should常表示劝告、建议、命令，与oughtto意义相近，但oughtto多表示责任、义务，语气强烈。,Everycitizenoughttoobeylaw.,Yououghtnottogo.,Youshould/oughttohavetoldherthetruthearlier.,Sheshouldnthaveleftwithoutsayingaword.,4.should/oughttohavedone表示责备或批评,意为“本应该但”,oughtto的语气更强烈,用于否定则表示“本不该但”,5.should用于可能性推测时,表“应该，很可能”,Theyleftat5:30.Theyshouldgettherenow.,.,18,1.作为情态动词用，常用在否定句和疑问句中。,Dare(need)+S+VS+darent(neednt)+V,Idarentwalkthroughtheforestatnight.Dareyouwalkthroughtheforestatnight?Youneedntreturnthebooknow.Needhegoyesterday?,六.可兼做行为动词的情态动词：need、dare,.,19,2.作实义动词用，常用在肯定句中,有人称、时态、和数的变化,Heneedstogotherehimself.Hehasgrownup,sowedontneedtoworryabouthim.,3.Sth(sb)need(want,request)+doing/tobedoneThehouseneedscleaning/tobecleanedTheboyneedssendingtothehospitalatonce.,.,20,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,对将来对现在对过去,情态动词,may,might,cant,couldnt,can,could,+V.+V.+havedone常见mustbe+bedoing,+V.+V.+havedone+bedoing可以用not表示“可能不”,+V.+V.+havedone+bedoing,+V.+V.+havedone+bedoing,.,21,Exercises,.,22,I.Trytoexplainthemeaningsofthemodalverbsinthefollowingsentences.1.HecanspeakEnglishwell.2.Youcangohomenow.3.Thatcantbetrue.4.CouldyoupleaseshowmethewaytoBeihaiPark?5.Theyhuntersarelost.Theycouldstarve.6.MayIcomein?7.Hemaygiveyousomehelp.,ability,permission,guessing,request,possibility,permission,possibility,.,23,8.Dontworry.Iwillhelpyou.9.Oftenhewoulddressuplikearichman.10.Wouldyouliketojoinusfordinner?YoushallhavetheticketassoonasIgetit.Youshouldarriveattheairporttwohoursbeforehegoes.Itisfiveoclock.Heshouldturnupsoon.WangFengwinsanawardeveryyear.Hemustbestrong.,promise,pasthabit,request,promise,prediction,advice,speculation,2.用情态动词完成句子1).Youvebeenworkingallday.You_beverytired.2).(Thedoorbellrings)Iwonderwhothatis.It_beLisa.Shesstillinthelibraryatthistime.3).Itisalongtimesincewemetlasttime.You_comeandseeusmoreoften.,must,cant,should,4.IhaventdecidedwhereImgoingformyholidays.I_gotoAustralia.5.Myfathersbirthdayiscoming.What_Igivehim?6.Whydontyoutryonthisdress?It_lookniceonyou.,may,shall,will,7.“Whowasthemantalkingwithyourteacher?”“Imnotsure.It_beherbrother.”8.Idontknowwhentheguests_behere.They_arriveatanytime.,might,will,could,3.完成下列句子：1.Idontknowwheresheis,she_.(可能在武汉）(be)2.Atthismoment,ourteacher_（想必在批改）ourexampapers.(mark/grade)3.Theroadiswet.It_(一定下雨了）lastnight.(rain)4.Yourmother_（一定一直在找你）(look),maybeinWuhan,gradingmustbemarking,musthaverained,musthavebeenlookingfor