《状语从句》课件.ppt

* 状语从句 状语从句在主从复合句中修饰主句中的动词，形容词或副词，按意义可分为时间、地点、原因、目的、结果、条件、方式、比较、让步等状语从句。 从句的位置放在句首，也可放在句末。放在句首时，从句后面常用一个逗号，放在句末时，从句前一般不用逗号。 ?? （1）when, as, while （从属连词） when即可引导持续性动作，又可引导短暂性动作。它可以表示主句的动作和从句的动作同时发生，或从句的动作发生在主句动作之前。如： When I was a boy, I used to go to the seashore on Sundays.（同时） When the lesson was over, we began our writing. （从句动作在前） 1、时间状语从句： 引导时间状语从句的从属连词有：when, while, as, whenever, before, after, since, till, until, as soon as, once,the moment, immediately, no sooner…than, hardly…when, by the time, every time, last time…等引导。 ??as引导持续性动作，侧重主句和从句的动作同时发生。 He hurried home, looking behind as he went. I saw your sister as she was getting on the bus yesterday. He sang as he walked. While：指的是“在某一时间里”，“在… 期间”，从句里的动作必须是持续性的，它也强调主句和从句动作的同时发生，往往侧重主句和从句动作的对比。 如： While he was in London, he studied music. While we were watching TV, he was writing a composition. 当when, as, while表示“在…一段时间里”，主从句的动作同时发生时，可以换用。如： While (When或As) we were discussing, Mr. Smith came in. *when 可表示“如果”。如： Don’t be afraid of asking for help_____ it is needed. (’03全国） A. Unless B. since C. although D. when *while可表示“虽然，尽管”。如： 1)____ modeling business is by no means easy to get into, the good model will always be in demand.(’04浙江） A. While B. Since C. As D. If 2)_____ I accept that he is not perfect, I do actually like the person.(’04江苏） A. While B. Since C. Before D. Unless When和while（并列连词），while表示对照的意思。When 表示“这时，突然…” I do every single bit of housework____ my husband Bob just does the dishes now and then.(’04广西） A. since B. while C. when D. as 2) He was about to tell me the secret____ some one patted him on the shoulder. (’02上海） A. as B. until C. while D. when 3) We were swimming in the lake ____ suddenly the storm started.(’04北京春招） A.When B. while C. until D. before 4) Jasmine was holidaying with her family in a wildlife park____she was bitten on the leg by a lion.