Unit7条件状语从句牛津深圳版英语八年级上册语法讲义

Unit7条件状语从句if引导的条件状语从句1.含义在复合句中作条件状语的从句称为条件状语从句。常见的if条件状语从句表示在某条件下，某事很可能发生，条件是可能存在的，主句中某种情况发生的概率也是很高的。if作连词，意为“如果”，引导条件状语从句。Ifitdoesn’traintomorrow,Iwillgoclimbingwithmyfriends.主句If引导的条件状语从句主句If引导的条件状语从句2.位置if条件状语从句可置于句首，要用逗号与主句隔开，也可置于句尾。例如：Ifitrainstomorrow,wewillnotgotothezoo.如果明天下雨的话，我们就不会去动物园（1）主句+if条件句。例如：Thecatwillscratchyouifyoupullhertail.如果你拉猫的尾巴，它就会抓你。（2）If条件句+逗号+主句。例如：Ifyoufailintheexam,youwilllethimdown.如果你考试不及格，你会让他失望的。3.时态主句从句一般将来时（will+动词原形）一般现在时情态动词（may/can/should/must+动词原形）一般现在时祈使句（动词原形开头）一般现在时一般现在时一般现在时（1）if从句用一般现在时，主句用一般将来时（主将从现）例如：Ifheruns,he’llgetthereintime.如果他用跑的，他就会及时赶到那儿。（2）if从句用一般现在时，主句用may/can/should/must+动词原形（主情从现）例如：Ifitstopssnowing,wecangoout.如果雪停了，我们就可以出去。Ifyouwanttoloseweight,youmust/shouldeatlessbread.如果你想减肥，你必须少吃面包。（3）if从句用一般现在时，主句用祈使句（主祈从现）例如：Putonyourcoatifyourarecold.如果你冷的话，穿上外套吧。Ifitrainstomorrow,pleasestayathome.如果明天下雨的话，请待在家里if从句用一般现在时表示的动作，导致主句动作的必定发生，主句用一般现在时（主现从现）4.if的双重用法if可以引导条件状语从句，意为“如果”，此时需注意“主将从现”的原则Ifitrainstomorrow,Iwon’te.if也可以引导宾语从句，意为“是否”，时态选用相对比较自由，不受“主将从现”原则的限定Idon’tknowifitwillraintomorrow.Unless引导的条件状语从句◆◆unless引导的条件状语从句：unless=if…not“除非......否则,如果不”①Let'sgooutforawalkunlessyouaretootired.=Ifyouarenottootied,let'sgooutforawalk.我们出去散步吧，除非你太累②Youwillfailtoarrivethereintimeunlessyoustartearlier.=Ifyoudon’tstartearlier,youwillfailtoarrivethereintime.如果你不早点动身,你就不能及时赶到那儿。③Unlessitrains,thegamewillbeplayed.=Ifitdoesn’train,thegamewillbeplayed.除非下雨,比赛将照常进行。④Mybabysisternevercriesunlesssheishungry.=Mybabysisternevercriesifsheisn’thungry.我的妹妹不会乱哭，除非她饿了。注意：unless引导的条件状语从句也要遵循“主将从现”，“主祈从现”及“主情从现”的规则。综合练习一、单选题()1.—Idon'tknowifit______tomorrow.—Well,ifit______,theschoolsportsmeetwillbecanceled.A.willrain,willrain B.rains,willrainC.willrain,rains D.rains,rains()2.We______forapicnicifit______rainthisSunday.A.willgo,doesn't B.willgo,won'tC.go,doesn't ()3.Iwonderifshe______mewhen______.A.calls,shearrives B.willcall,shearrivesC.calls,willshearrive()4.—CouldyoutellmewhenMr.Li______inDaqing?—Sure.Whenhe______,I'llcallyou.A.es,esB.wille,esC.es,willeD.e,es()5.Weplantohaveapicnictomorrow,soIwonderif______.A.willitrain B.itrains C.itwillrain()6.Ifyouclosethedoorofsadnessbehindyou,thedoorofhappiness______beforeyou.A.opened B.haveopenedC.willopen D.areopening()7.—CanyouguessifMike______swimmingthisafternoon?—Ithinkhewillgowithusifhe______free.A.willgo,is B.willgo,willbeC.goes,isD.goes,willbe()8.Ithinkit'snecessaryformydaughtertohaveherownmobilephone,forIsometimeswanttomakesureifshe______homefordinner.A.e B.es C.hase D.wille()9.I'mnotsureifhe___inthisexam.Butifhe___harder,hewilldobetter.A.succeeds,works B.willsucceed,willworkC.willsucceed,works D.succeeds,willwork()10.Jeff____thehospitalifhefeelsbetterinafewdays.A.leaves B.left C.willleave D.hasleft()11.—Doyouknowwhattimeyouruncle_____Hangzhoutomorrow?—At2:00p.m.Iwillmeethimwhenhe_____attheairport.A.getsto,arrives B.willgetto,willarriveC.willgetto,arrives D.getsto,willarrive()12.—Hi,doyouknowifTom_____tomypartynextweek?—Ithinkhewilleifhe____free.A.wille,willbe B.wille,isC.e,is D.e,willbe()13.We'renotsureifit_____tomorrow.Ifit_____,wewon'tgohiking.A.willrain,rains B.willrain,willrainC.rains,rains D.rains,willrain()14.It_____long____weknowtheresultoftheexperiment.A.willnotbe,before B.is,sinceC.willnotbe,until D.hasbeen,after()15.It'sbeyonddoubt___itwill___laterintheday.Takearaincoatwithyou.A.that,berain B.whether,berainC.that,berainy D.if,haverain当堂练习一、单选题()1.—Doyouknowwhen_____yourparents?—Idon'tknow.Butifthey_____,Iwilltellyou.A.wille,e B.wille,willeC.e,wille D.e,e()2.—Amy,doyouknowifDaniel_____tothefarmwithustomorrowifit____?—Sorry,I'venoidea.A.willgo,willrain B.willgo,rainsC.goes,willrain D.goes,rains()3.Ihearthere____atalkonthehistoryofChinaatthehall____April20th.A.willhave,in B.willbe,onC.isgoingtohave,until D.isgoingtobe,at()4.—Doyouknowwhenyourmother_____?—Idon'tknow.Butifshe_____,I'lltellyou.A.wille,es B.wille,willeC.es,wille D.es,es()5.—Theradiosaysit_____alottomorrow.—That'stoobad.It_____soofteninsummerinSuqian.A.willrain,rains B.rains,willrainC.willrain,isgoingtorainD.rains,rains()6.—Mum,doyouknowifDad_____amodelplaneforme?—Ithinkhewilldoifhe_____free.A.willmake,willbe B.makes,isC.makes,willbe D.willmake,is()7.Mike______thegoodnewstohismotherassoonashe______hismotherafterschool.A.willtell;sees B.tells;sees C.tell;see D.willtell;willsee()8.Wewillgoforapicnic_______itissunnytomorrow.A.when B.whether C.if D.while()9.Mariawillspendtimewithherfamilyassoonasshe_____time.A.willhave B.have C.has D.had()10.ThetrafficinShanghaiwillbeebetterifeveryonethetrafficrules.A.willobey B.isobeying C.obey D.obeys()11.IfMarylatetomorrow，theteacherwon'tletherin.A.is B.willbe C.be D.was()12.Iwon'tgotoLinda'spartyunless.A.Iwillbeinvited B.Iaminvited C.Iwillnotbeinvited D.Iamnotinvited()13.JameswiththeGreenstheWhiteTowerParkifittomorrow.A.aregoingto;isn'trainy B.aregoingto;doesn'train C.isgoingto;won'train D.isgoingto;isn'trainy()14.—Whatwillyoudo_______itdoesn'traintomorrow.—We'llhaveapicnic.A.until B.because C.if D.though()15.—Frankcouldwepainttheroomtogethertomorrow?—Sure,ifI______freetomorrow.A.be B.willbe C.am D.amgoingtobe课后巩固()1.—Shallwegoforapicnictomorrow?—Ifitrain.A.isn't B.won't C.don't D.doesn't()2.IwillwatchTVinsteadofswimmingoutsideassoonasittomorrow.A.rains B.willrain C.rained D.haverained()3.Ifit_______tomorrow,weshallgoonfoot.A.notrain B.don'train C.rain D.doesn'train()4.Mybrotherwilldothisjobbetterifhe______howtouseaputer.A.willknow B.knows C.know D.knew()5.—Whatareyougoingtodothisweekend,Daming?—Iwillhaveapicnicwithmyfriendifit.A.rains B.won'train C.doesn'train D.isn'train()6.—Yourauntwillwalkthedogtomorrowmorning.—Yeah,unlessbadweather________her.A.stops B.willstop C.tostop D.stop()7.Iwillsendyouane﹣mai1assoonasI_____inAustralia.A.arrive B.arrived C.amarriving D.willarrive()8.MysisterhaslearnedEnglish.A.fortwelveyearsago B.sinceshewasfour C.twelveyearsago D.attheagooffour()9.Don'tworryaboutme,mum.I'llwritetoyouassoonasIschool.A.willgetto B.arriveat C.willreach()10.We