Unit2Let'sCelebrate!UsinglanguageGrammar课件高一英语

外研必修第二册UsinglangugeUnit2Let'scelebrate!aThatiswhyLettersfromFatherChristmas

couldbetheperfectbook...b

Thechildrenmusthavebeenveryexcitedastheyopenit.c...theymightnotreceivetheirpresentsiftheywerenotgood.Thewordsinredare___________.Whatdothewordsinredindicate:anorder,arequest,abilityorpossibilityLookatthesentencesfromthereadingpassageandanswerthequestions.Willthemeaningofsentence(a)changeifwereplace“could”with“must”or“might”Whathappensifwechange“must”and“might”insentences(b)and(c)into“could”Nowlet'sreadmoreexamples.Thespeakerisquitesureaboutthestatement.“Could”and“might”haveasimilarmeaningwhenindicatingpossibility.modalverbsmustmightcouldcouldThespeaker

isnotsureaboutthestatement,andit'sonlyapossibility.It's

impossibleforthechildrentoreceivetheirpresents.1.Theletterswerealsobeautifully-illustrated-eachmusthavetakenitstrueauthor,Tolkien,alongtimetocomplete.2.Inanotherletter,FatherChristmascomplainedabouthowhecouldnot

stophishelpersplayinggameswiththetoysinsteadofwrappingthemup.3....othercharactersattheNorthPole,wecan

sharethetruespiritofgivingatChristmastime.4....TolkienmayhavebeentherealFatherChristmas.1.Theletterswerealsobeautifully-illustrated-each_______________(take)itstrueauthor,Tolkien,alongtimetocomplete.2.Inanotherletter,FatherChristmascomplainedabouthowhe____________(stop)hishelpersplayinggameswiththetoysinsteadofwrappingthemup.3....othercharactersattheNorthPole,we___________(share)thetruespiritofgivingatChristmastime.4....Tolkien______________(be)therealFatherChristmas.Fillintheblankswithappropriatewords.cansharecouldnotstopmusthavetakengoReadymayhavebeenFocuson基本用法情态动词must,can,could,may,might等都有表推测的用法，都可以对过去，现在或将来的情况是否发生做出语气强弱不同的推测。情态动词表推测1根据推测语气的强弱，选择情态动词。1.在肯定句中表推测:(1)Youmusttellmeallaboutyournewfriend.

(2)Hecouldbeathome.Hemaybeathome.Hemightbeathome.你必须告诉我有关你新朋友的一切。他可能在家。could,may,might语气依次减弱，表示“可能，也许”。must语气最强，表示“肯定，一定”；(非常肯定)（很可能）（仅仅可能而已）（或许，非常不确定）2.在否定句中表推测:(1)Itcan'tsnowinsummer.may/mightnot语气较弱，表示“可能不”；mustn't表示“禁止”，不用于否定推测。我们可能哪里也去不成。(2)Wemightnotgoanywhere.Youmustn'ttellalietoparents.夏天不可能下雪。你不能对父母说谎。can't,couldn't语气较强，表示“不可能”；3.在疑问句中表推测:(1)Couldhehavefinishedthetask他可能把任务完成了吗？(2)Canhebeathomenow他现在能在家吗？（语气较为委婉，可能性较小）（语气较强）疑问句中用can/could（能……？），could语气更加委婉不确定。2情态动词表推测的三种时态。1.“情态动词+be/bedoing/动词原形”表达对现在情况或此时此刻正在发生的事情的推测。(3)Hemust

workveryhard.(=I'msurehegenerallyworksveryhard.)他一定工作很努力。(2)Theymaynotbehavingfun.(=Idon'tthinktheyarehavingfun.)他们可能并不开心。(1)Hecan'tbeathomeatthistime.(=Idon'tthinkheisathomeatthistime.)这个时候他不可能在家。2.“情态动词+动词原形”表达对将来情况的推测。 (1)Shemustarrivebefore5.

(=I'msureshewillarrivebefore5.)5:00前她一定到。(2)Shemaywalkmilesandmilesamongthehillswithoutmeetinganyone.(=It'sprobablethatshewalkmilesandmilesamongthehillswithoutmeetinganyone.)她可能会在山里一连走好几英里都遇不到一个人。(1)may/mighthavedone

3.“情态动词+have+V-ed”①Theymighthavegotlost.②Youmayhavemisheardher─I'msureshedidn'tmeanthat.他们可能迷路了。表示对已发生事情的不肯定推测你可能听错她的话了——我肯定她不是这个意思。①Emmamusthavebeenveryupset.②Ithinkwemusthavetakenawrongturningsomewhere.(2)musthavedone

表示对已发生情况的推测，通常用于肯定句艾玛一定很难过。我觉得我们一定是在什么地方拐错了路。might比may更加不确定①Youcan’thaveforgottenher.②Wherecanshehaveputit(3)canhavedone

表示对已发生情况的推测，通常用于否定句或疑问句你不可能已经忘了她。她到底把它放在哪儿了呢？①Couldshehaveforgottenmyaddress②Hecouldnothavebeenmorethan16atthattime.(4)couldhavedone

表示对过去情况的推测，多用于否定句或疑问句她会忘记我的地址吗？他当时不可能超过16岁。情态动词表推测时的反意疑问句、附加疑问句部分一般不再用情态动词表示推测语气。而是根据情态动词之后的动词及时间状语或上下文确定具体形式。(1)Thatgirlmustbeyoursister,isn'tshe(2)Hemusthaveleftyesterday,didn'the那个女孩一定是你的妹妹，是吗他昨天一定走了，是吗Rewritetheunderlinedsentencesintheconversationusingcan/could,may/might

andmust.Possibleanswers!Youmustbetirednow!Itmay/might/couldbehim.ThatmustbeLucy.Thatcan'tbeLucy.Theymay/might/couldbefromourschool.P172Lookatthepictureandmakeasmanysentencesaspossibleusingcan/could,may/might

andmust.Themanwithawalletinhishandmightbeabitreluctanttopay.Thecashiermightbefeelinguncomfortableasheissweatingalot.Possibleanswers!Thewomanwithglassesmaybeverytiredtogetupsoearlyandcarrysomanybags.P1731.（2022天津卷3月）Itusedtobethatyou___driveformilesherewithoutseeinganotherperson,butnowtherearehousesandpeopleeverywhere.A.need B.should C.could D.must4.（2018天津卷）Ican'tfindmypurse.I___itinthesupermarketyesterday,butI'mnotsure.A.shouldleave B.musthaveleftC.mightleave D.couldhaveleft2.（2019天津卷）Mywalletwasgone._________________________________.（我只可能把它落在了G9公共汽车上。）IcouldonlyhaveleftitontheG9bus3.（2018北京卷）Intoday'sinformationage,thelossofdata____causeseriousproblemsforacompany.A.need B.shouldC.can D.mustGrammarFocus情态动词表推测三种时态过去现在情态动词+have+V-ed情态动词+be/bedoing/动词原形将来情态动词+动词原形根据语气强弱选择肯定句否定句must最强can't,couldn't最强could,may,might依次减弱may/mightnot较弱can语气较强could语气更加委婉不确定疑问句注：另附word文档，点此链接。Ⅰ.选择括号内适当的内容填空。1.Itistoolatetogoback.We_________(may/must)goon.2.Thetemperatureinthemountains_________(must/can)beverylowatnight,soyou'dbettertakesomemoreclothes.3.Thelightisnoton.TheGreens_________(mustn't/can't)beathomenow.4.Hesaidhe_________(might/can)cometomorrow,butIamnotsureaboutthat.5.Yoursisterboughtsomuchfruit.She_________(must/shall)likeeatingit.mustcancan'tmightmustⅡ.根据汉语提示完成句子。1.Yourson___________________(可能正在做)hishomeworkathomenow.2.It_________________(肯定是)David,becausehehasjustcalledmesayingthathewillvisitus.3.Sincetheroadiswet,it_________________(肯定下雨了)lastnight.4.He__________________________(不可能迷路).Idrewhimamap.5.Mary____________________(可能不知道)thesecret.may/mightbedoingmustbemusthaverainedcan't/couldn'thavegotlostmay/mightnotknowⅢ.用can,must或might的适当形式完成对话。1.—Areyougoingtoa