when和while的结构
when和while的语法结构？
when和while的语法结构？
when后面可以加进行时或非进行时的句子；而while后面的句子用进行时态或状态性动词的一本时。例如 When his mother arrived,he was reading. When it was raining,I was watching TV.
While she was reading,I was writing.
While he was away from his home,he missed his family very much.
when和while的用法详解？
when和while的用法与区别：1、由when引导的时间状语从句,主句用过去进行时,从句应用一般过去时；如果从句和主句的动作同时发生,两句都用过去进行时的时候,多用while引导,如：a.Whentheteachercamein,weweretalking.当此句改变主从句的位置时,则为：Whileweweretalking,theteachercamein.b.Theyweresingingwhileweweredancing.2、when和while还可作并列连词.when表示“在那时”；while表示“而,却”,表对照关系.如：a.Thechildrenwererunningtomovethebagofricewhentheyheardthesoundofamotorbike.孩子们正要跑过去搬开那袋米,这时他们听到了摩托车的声音.b.Heisstrongwhilehisbrotherisweak.他长得很结实,而他弟弟却很瘦弱.3、when,while引导时间状语从句的区别一、when可以和延续性动词连用,也可以和短暂性动词连用；而while只能和延续性动词连用.①Whydoyouwantanewjobwhenyouvegotsuchagoodonealready?（get为短暂性动词）你已经找到如此好的工作,为何还想再找新的?②Sorry,Iwasoutwhenyoucalledme．（call为短暂性动词）对不起,你打电话时我刚好外出了.③Strikewhiletheironishot．（is为延续性动词,表示一种持续的状态）趁热打铁.二、when从句的谓语动词可以在主句谓语动作之前、之后或同时发生；while从句的谓语动作必须是和主句谓语动作同时发生.1．从句动作在主句动作前发生,只用when.①Whenhehadfinishedhishomework,hetookashortrest．（finished先发生）当他完成作业后,他休息了一会儿.②WhenIgottotheairport,theguestshadleft．（gotto后发生）当我赶到飞机场时,客人们已经离开了.2．从句动作和主句动作同时发生,且从句动作为延续性动词时,when,while都可使用.①When／Whileweweredancing,astrangercamein．（dance为延续性动词）当我们跳舞时,一位陌生人走了进来.②When／Whileshewasmakingaphonecall,Iwaswritingaletter．（make为延续性动词）当她在打电话时,我正在写信.4．在将来时从句中,常用when,且从句须用一般时代替将来时.①YoushallborrowthebookwhenIhavefinishedreadingit．在我读完这本书后,你可以借阅.②Whenthemanagercomeshereforavisitnextweek,Illtalkwithhimaboutthis．下周,经理来这参观时,我会和他谈谈此事.三、when用于表示“一……就……”的句型中（指过去的事情）.sb．hadhardly（＝scarcely）donesth．when．．．＝Hardly／Scarcelyhadsb．donesth．when．．．①Ihadhardly／scarcelyclosedmyeyeswhensomeoneknockedatthedoor．＝Hardly／ScarcelyhadIclosedmyeyeswhensomeoneknockedatthedoor．我刚一闭上眼,就有人在敲门了.②Ihadhardly／scarcelyenteredmyroomwhenthetelephonerang．＝Hardly／ScarcelyhadIenteredmyroomwhenthetelephonerang．我刚一走进房门,电话就响了.