单元语法归纳1.before“在……之前”,引导时间状语从句时,表示主句动作发生在从句动作之前。注意before引导的从句一般不用否定式的谓语,并且当before引导的从句位于主句之后时,有时译成“就,才”。还要注意主句和从句之间的时间关系。当主句用将来时,从句一般用现在时;如果before引导的从句谓语用的是过去时,则主句动词多用过去完成时,这样以便体现动作发生的先后。before,after,as引导的时间状语从句2.after“在……之后”,引导时间状语从句时,表示主句的动作发生在从句的动作之后。主句和从句的动作的时间关系正好与before引导的从句相反。例如:Itwillbefourdaysbeforetheycomeback.他们要过四天才能回来。MyfatherhadleftforCanadajustbeforetheletterarrived.我父亲恰好在信件到达之前去加拿大了。Afterwehadfinishedthework,wewenthome.完成工作之后,我们回家了。(从句用过去完成时,主句用一般过去时)3.as表示“一边……一边”,as引导的动作是延续性的动作,一般用于主句和从句动作同时发生;as也可以强调“一先一后”。例如:Wealwayssingaswewalk.我们总是边走边唱。(as表示“一边……一边”)Asweweregoingout,itbegantosnow.当我们正要出门时,开始下雪了。(as强调句中两个动作紧接着先后发生,而不强调开始下雪的特定时间)一、用before,after,as填空1.HehadlearnedChinesehecametoChina.2.finishingthework,wesatdowntosumupexperience.3.Shelikeseverythingtobeinplaceshestartstowork.4.Theydecidedtogobackhometheirmoneyranout.5.Isawherjustshewasgettingoffthetrain.beforeAfterbeforebeforeas二、单项选择()6.ItwaseveningwereachedthelittletownofWinchester.A.thatB.untilC.sinceD.before()7.—Whydidn’tyoutellhimaboutthemeeting?—HerushedoutoftheclassroomIcouldsayaword.A.beforeB.untilC.whenD.after()8.wegottothestation,thebuscame.A.BeforeB.BecauseC.AsD.Since()9.Itwasquietthosebigtrucksstartedcomingthroughthetown.A.beforeB.afterC.untilD.unless()10.Thestudentsweretalkingtheteachercamein.A.untilB.afterC.asD.beforeDACAC单项选择()1.Thesesentencesareveryimportant;youmust.A.writedownitB.writeitdownC.writethemdownD.writedownthem()2.Theideasounds;weallagreeonit.A.wellB.goodC.badlyD.bad()3.“Haveyoureadtoday’snewspaper?”“Yes.It’sreallyboring.Thereisinit.”(2014贵阳)A.somethingnewB.no...
