时间和原因状语从句

Unit4Grammar(1)时间状语从句：引导时间状语从句的连词有：when,while,as,before,after,till,until,since,assoonas,themoment,immediately,everytime,nexttime,thefirsttime,once等。when,while,as表“当...时”的异同：相同点:当从句的谓语是延续性动词时，三者常可互换i.e.When/While/Aswewerestilllaughing,theteachercamein.不同点:1)when既表“时间段”又表“时间点”(=duringoratthetimethat),从句中动词既可是终止性的，也可是持续性的，还可表“正在这时”i.e.(1).WhenIarrivedthere,theywerewatchingTV.(2).WhenIwasyoung,Ilikedsinginganddancing.2)while只表“时间段”(=duringthetimethat),从句中动词只限于持续性动词，它有时含对照之意，表“然”而i.e.(1)Hefellasleepwhilehewasstudyinghisgrammarbook.3)as用法与when相似，但它侧重动作的同时性，表“一边...一边...”，还表“随着”i.e.(1)Theytalkedastheywalked.(2)Astimegoesby,wegetwiser.1.when---正在…的时候，突然…IwaswalkingalongthestreetwhenImethim.Oneevening,littleHanswassittingnearthefirewhenheheardaloudknockatthedoor.Iwasabouttofallasleepwhenmysistercamein.Hehadjustgotbackhomewhenthetelephonerang.我正准备告诉他那个秘密，这时有人拍了拍我的肩膀。Iwasabouttotellhimthesecretwhensomeonepattedmeontheshoulder.Ihadhardlygothomewhenitbegantorain.HardlyhadIgothomewhenitbegantorain.1.Hetransplantedthelittletreetothegarden______itwasthebesttimeforit.A.whereB.whenC.thatD.until2.---DidJackcomebackearlylastnight?---Yes.Itwasnotyeteighto’clock____hearrivedhome.A.beforeB.whenC.thatD.until3.Hewasabouthalfwaythroughhismeal______afamiliarvoicecametohisears.A.whyB.whereC.whenD.while1)ThecostoflivinginGlasgowisamongthelowestinBritain,______thequalityoflifeisprobablyoneofthehighest.A.sinceB.whenC.asD.while2)______Iacceptthatheisnotperfect,Idoactuallyliketheperson.A.WhileB.SinceC.BeforeD.Unless2.连接词while的用法小结1)while引导的动作必须是持续性的，侧重主句动作和从句动作相对比。如：Pleasedon’ttalksoloudwhileothersareworking.2)while作为并列连词，意为“而，却”，表示对比。3)while可表示尽管，相当于although。1.WhileIwaswaitingforTom,threebuseswentby.2.Idoeverysinglebitofhousework,whilemyhusbandBobjustdoesthedishesnowandthen.3.Whilemodelingbusinessisbynomeanseasytogetinto,thegoodmodelwillalwaysbeindemand.when/whiledoing:1)When/WhileIwaslookingthroughthepaper,InoticedafewgrammaticalmistakesWhen/Whilelookingthroughthepaper,Inoticedafewgrammaticalmistakes.2)Whilehewaswanderingthroughthesquare,hecaughtsightofasnake-charmerWhilewanderingthroughthesquare,hecaughtsightofasnake-charmerwhen/whiledoneWhenweweretakenroundthecity,wewereimpressedbythecity'snewlook.Whentakenroundthecity,wewereimpressedbythecity'snewlook.3.not…until---直到……才Hedidn’tgetoffthebusuntilitstopped.Notuntilthebusstoppeddidhegetoffit.Itwasnotuntilthebusstoppedthathegotoffit.直到被送入手术间时，他才明白遵守交通规则的重要性。Hedidn'trealizetheimportanceofobservingthetrafficregulationsuntilhewassentintotheoperatingroom.1.---Washisfatherverystrictwithhimwhenhewasatschool?---Yes.Hehadneverpraisedhim___hebecameoneofthetopstudentsinhisgrade.A.afterB.unlessC.untilD.when2.Agoodstorytellermustbeabletoholdlisteners’curiosity___hereachestheendofthestory.A.whenB.unlessC.afterD.until3.Itwasnot___shetookoffherdarkglasses___Irealizedshewasafamousfilmstar.A.when;thatB.until;thatC.until;whenD.when;then小结：till,until和not…until：1.until/till引导时间状语从句用于肯定句时，主句的动词是延续性动词，表示动作或状态一直持续到until/till所表示的时间，意为“某动作一直延续到某时间点才停止”。如：Wewaiteduntilhecame.2．用于否定句时，主句谓语动词是非延续性动词，从句为肯定，意为“某动作直到某时间才开始”。如：Theboywon’tgotobedtill/untilhismumreturns.3．till不可以置于句首，而until可以。如：UntilyoutoldmeIhadnoideaofit.4．not…until句型中的强调和倒装说法：ItwasnotuntilyoutoldmethatIhadanyideaofit.NotuntilyoutoldmedidIhaveanyideaofit.4.before---在……之前HeranoffbeforeIcouldstophim.现在就做，免得你忘记了。Doitnowbeforeyouforgetit.几个星期过去了我才意识到那幅画丢了。SeveralweekshadgonebybeforeIrealizedthepaintingwasmissing.ItwasnotlongbeforeIforgotitall.五年后我们才会再见面呢。Itwillbefiveyearsbeforewemeetagain.我们将作进一步的讨论，然后再作出最终的结论。Wewillhaveafurtherdiscussionbeforewedraw/makeafinalconclusion.1.Hemadeamistake,butthenhecorrectedthesituation___itgotworse.A.untilB.whenC.beforeD.as2.Scientistssayitmaybefiveorsixyears____itispossibletotestthismedicineonhumanpatients.A.sinceB.afterC.beforeD.when3.---Whydidn’tyoutellhimaboutthemeeting?---Herushedoutoftheroom___Icouldsayaword.A.beforeB.untilC.whenD.after4.Itisalmostfiveyears___wesaweachotherlasttime.A.beforeB.sinceC.afterD.because连接词before的小结：1.Wehadsailedfourdaysandfournightsbeforewesawland.2.Wehadn’trunamilebeforehefelttired.3.Pleasewriteitdownbeforeyouforgetit.4.BeforeIcouldgetinaword,hehadmeasuredme.Before从句中谓语不用否定式。如：Beforetheyreachedthestation,thetrainhadgone.1)句型Itwillbe/was＋段时间＋before…“还要过多久才…”Itwillbetwoyearsbeforeheleavesthecountry.2)句型Itwillbe/wasnot＋段时间＋before…“不多久就…”Itwasn’ttwoyearsbeforeheleftthecountry.3)句型Itis＋段时间＋since…时间的计算一律从since从句的动作完成或状态结束时算起。Itisthreeyearssinceshewasinthearmy.Itisthreeyearssinceshejoinedthearmy.1)Applyitafterwettingyourhairwithwarmwater.Youapplyitafteryouwetyourhairwithwarmwater2)Aftershampooing,squeezeouttheextrawaterandapplyconditioner.Afteryoushampoo,yousqueezeouttheextrawaterandapplyconditioner3)Afterwashingouttheshampoo,applytheconditionerandcombitintoyourhair...Afteryouwashouttheshampoo,youapplytheconditionerandcombitintoyourhair...4)Beforetheywereshownaroundit,thevisitorswatchedavideoaboutthemuseum.Beforebeingshownaroundit,thevisitorswatchedavideoaboutthemuseum.before/afterdoing/beingdone5.s