Unit3Languageinuse导学目标：1.掌握情态动词must,can,could表推测。2.掌握祈使句的用法。自主预习：一、根据句意及首字母补全单词1.K_________moneyinasafeplace.2.Weplayedbasketballi_________becauseitrained.3.I'llhearafootsteponthes__________.4.Earthquakeisveryc____________inJapan.5.Manyearthquakescancausealotofd__________.6.Theyc____________peoplefromthebeach.二、选用方框中的介词完成句子on,by,about,from,of,off1.Peoplearetryingtocleartherocks_____theroads.2.Shelearnt__________underwaterearthquake.3.Theyclearedpeople______thebeachjustminutesbeforeahugewavereachedtheland.4.ImetmyfriendTom_______mywayhome.5.Ourparentsareproud_______us.6.Aten-year-oldgirlsavedaboutonehundredothertouristsin2004_________warningthemthatahugeoceanwavewascomingacrossthesea.课堂导学：1.情态动词must,can,could表示推测情态动词can,could表示“能够，可以”等意义,can,could还表示对现在或将来的推测。意为“会，可能”。（1）can表示推测时，往往用于否定句和疑问句。用于疑问句时，can比could表示的“可能性”要大；用于否定句时，can’t表示“不可能”。例如：Youcan’tbeserious!你不是认真的吧！（2）could则可用于肯定句、否定句和疑问句，表示某事有可能发生或可能是事实例如:Hecouldbeinpain.他可能很疼。Can/Couldthisbetrue?这有可能是真的吗？（3）情态动词must也可以表示猜测，意思为“一定、准是”，通常只能用于肯定句。例如：Betty,youmustknow!贝蒂，你肯定知道！辨析：（1）Whosentthepresent?Canitbeyourbrother?是谁送来的礼物啊？会是你哥哥吗？（询问可能性）（2）Itmustbeyourbrother.肯定是你哥哥。（语气强烈，表示非常肯定）（3）Itcan’tbemybrother.HisstillinFrance.不可能是我哥哥，他还在法国。（表示不肯能）2.祈使句表达说话人对对方的叮嘱、劝告、希望、禁止、建议、请求或命令等。祈使句一般以动词原形开头，无时态和数的变化。常见的句型如下：1.动词原形构成的祈使句此类祈使句暗含的主语是you,但通常省略。祈使句的句首或句末有时加please,还可以加上称呼语，用逗号与句子主体隔开。例如：Haveaniceday!祝你度过美好的一天！Comethisway,please.请走这边。Pleasebequiet,boys!男孩们，请安静！Makesurehe’swarm.确保他不受凉。祈使句否定形式往往在句首加上donot(don’t)或never。例如：Don’tusethelift.不要使用电梯。Neverbelateagain!再也不要迟到了！2.let’s构成的祈使句这类祈使句往往用于提出建议，例如：Let’sspendthisweekendinthecountryside.这周我们到乡下度周末吧。祈使句否定形式是当祈使句表示邀请或建议(Let’s…)时，则在Let’s与do之间加not。例如：Let’snothurry.我们不要太急。3.无动词祈使句在请求、命令和口号中，常用无动词祈使句，它实际上是省略了动词，从而使祈使句更简洁有力。例如：Justaminute,please!请稍等！Thisway,please!请走这边！祈使句否定形式是句首加not.例如：Notthere!不是那儿!当堂达标：单项选择（语法专练）()1.---Lookattheboyrunningontheground.IsitDavis?---It____behim.Isawhimgototheteacher’sofficejustnow.A.mustB.can’tC.couldD.might()2.Herdoctorsaid,“________worksohard”A.StopB.Don’tC.Can’tD.No()3.________inbed.It’sbadforyoureyes.A.NottoreadB.Don’treadC.Don’ttoreadD.Notread()4.________whenyoucrosstheroad.A.DocareB.CareC.BecarefulD.Tobecareful()5.________yourchild.We’lllookafterhim.A.NottoworryaboutB.Don’tworryaboutC.NotworryforD.Don’tworrywith()6.—Doyoubelievewhathesays? —Yes，it__________betrue.A.canB.couldC.needD.hasto()7.Thebookontheteacher’sdesk_____yours.Yournameseemstobeonit.A.maybeB.mustbeC.mayisD.hastobe()8.LiYing____________beherenowasshewenttoBeijingthreedaysago.Acan’tBneedn’tCmustn’tDmaynot()9.---Thelakeissaidtobedry.Isthattrue?---It________.Look,somekidsareswimminginit.A.mustbetrue.B.can’tbetrueC.maynotbetrueD.canbetrue()10.---David,isthatmanyourheadteacher?---It_____behim.He’sthetallestinourschool.A.mustn’tB.can’tC.needn’tD.won’t课后提高：一、用所给单词的适当形式填空1.Theearthcanriseandfallbeneaththebuildingwithout______________(shake)it.2.___________(luck),mymumwasathome.3.Peoplemuststayinsidetokeepawayfrom_______(fall)rocks.4.Doyoukeepthem___________(warmly).5.Don’tmovethemtoa____________(comfortably)place。二、根据要求完成句子1.Thegovernmentiswarningpeopleaboutanearthquake.(划线部分提问)_________________thegovernment_________?2.Thechildrendidn’tgototheplaygroundbecauseitrained.(同义句转换)Thechildrendidn’tgototheplayground_________________rain.3.Thereissomethingwrongwiththeradio.(改为否定句)There_________________wrongwiththeradio.4.ShewenttoLondonbyairyesterday.（划线部分提问）____________she______toLondonyesterday？5.Let’sgoswimming.(改为否定句)Let’s__________________swimming.四.阅读理解Whensomeplatesoftheearthmovesuddenly,anearthquakehappens.Manyearthquakesbeginunderthesea.Earthquakesmayhappenanywhereontheearth.Theyoftenhappennearthemountains. Duringanearthquake,theshakingsmakerocksrisesuddenlyandevencrack(断裂)open.Housesfall,peoplearekilledorhurt,andsometimesthewholevillagesorcitiesaredestroyed. Canwedosomethingtokeepourselvessafefromearthquakes?Scientistshavestudiedearthquakesandmakemapsthatshowthe“earthquakebelts”.Inareas(地区)inthesebelts,it’spossibleforearthquakestohappen.Intheseareasweshouldbuildstronghousestofightagainstearthquakes. Inthefuture,scientistswillbeabletotellwhenandwhereanearthquakewillbebeforetheyhappen.Theycanalsotellpeoplewhattodoandhowtodoit.1.Alargenumberofearthquakesoftenhappens_____.A.intheareaB.onlandC.atnightD.nexttomountains2.Thereasonforanearthquakeis_______.A.theresultofrockplatesuddenmovementB.thattherearesomanyplatesontheearthC.thattheseaistoodeepD.rocks’crackingopen3.Amapshowingtheearthquakebeltswilltellpeople______.A.whatkindofhousestobuildB.whatkindofhousescanstayupinanearthquakeC.whereearthquakemayhappenD.howtokeepthemselvessafeduringanearthquake4.Inthefuturewe’llbenolongersoafraidofearthquakes______.A.withthehelpofscientists’exactprediction(预报)B.becauseofamapshowingthe“earthquakebelts”C.becausewecanguessthedateandplaceofearthquakesD.asscientistsknowwhattodoandhowtodoit5.Choosethebesttitleforthepassage.A.AnEarthquakeB.AScientistandanEarthquakeC.HowtoFightAgainstEarthquakeD.EarthquakesTodayandTomorrow五，作文。 请以你的切身经历就这个问题Whatshouldwe