PAGE５状语从句在复合句中作状语，位置灵活。状语从句可分为时间状语从句，目的状语从句，条件状语从句，让步状语从句，地点状语从句，原因状语从句，方式状语从句，结果状语从句。时间状语从句when,as,whilewhen表时间，从句既可以用延续性动词，又可以用瞬间动词。Eg:WhenIgetthereIwillcallyou.如果when引导的时状的主语与主句的主语相同，而从句的谓语又是be动词时，那么从句中的主语与be可省。Eg：When（youare）introuble,youcanaskherforhelp.如果when引导的时状的主语与主句的主语相同时，往往可以用“when+分词”的形式代替该状从。Eg：WhenIcameintotheroom(Whencomingintotheroom),Ifoundthelightwasoff.while表时间，从句需用延续性动词，或者主句的动作发生在从句的动作进行过程中。主句的谓语动词通常是非延续性动词。Eg:HecameinwhileIwasreadingabook.ImetherwhileIwasinschool.c.as表时间，与when相似，但侧重强调主从句动作同在时间点或同时间段进行。同时可表示主句的动作随着从句的动作的变化而变化。Eg:Hejumpsashesings.Asthewindrose,thenoiseincreased.before(在……之前)与after（在……之后）Eg：Seemebeforeyouleave.IsawthemafterIarrived.3.till与until肯定形式表示的意思是"做某事直至某时"。否定形式表达的意思是"直至某时才做某事"。Eg:Waittill/untillIcallyou.等着直到我叫你。Shedidn'tarrivetill/until6o'clock..她直到6点才到但是置于句首时只可用untill.Untilyoutoldme,Ihadheardnothingofwhathappened.直到你告诉我以前，出了什么事我一点也不知道。否定形式有另外两种表达方式：(1)Notuntil…在句首，主句用倒装。Mandidnotknowwhatheatwasuntiltheearlyyearsofthe19thcentury.=Notuntiltheearlyyearsofthe19thcenturydidmanknowwhatheatwas.(2)Itisnotuntil…that…Hewillnotgotobeduntilhismothercomeshome.=Itisnotuntilhismothercomeshomethathewillgotobed.4.assoonas/themoment/theinstant/thesecond/theminute/immediately和hardly/scarcely…when,nosooner…thana.assoonas/themoment/theinstant/thesecond/theminute/immediately表示主句和从句的动作同时发生。译为“一……就”Eg：Assoonassheheardthenews,shebegancrying.b.hardly/scarcely…when,nosooner…than都可以表示"一……就……"的意思，但主句谓语动词一般要用过去完成时，从句谓语动词要用一般过去时。Eg：Ihadhardly/scarcelygothomewhenitbegantorain.Ihadnosoonergothomethanitbegantorain.注意：如果hardly,scarcely或nosooner置于句首，句子必须用倒装结构：Hardly/ScarcelyhadIgothomewhenitbegantorain.NosoonerhadIgothomethanitbegantorain。1.WecalledtheFirst-AidCenter_______thetrafficaccidenthappened.A.immediatelyB.shortlyC.quicklyD.hurriedly2.Therooffell_____hehadtimetodashintotheroomtosavehisbaby.A.beforeB.asC.afterD.until3.Agoodstorytellermustbeabletoholdhislisteners’curiosityhereachestheendofthestory.AwhenB