文档介绍：状语从句状语从句按其意义和作用可分为: 1. 时间状语从句 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, hardly … when, no sooner … than 等引导。如: When he was still a young man , he was forced to leave his homeland for political reasons. It has been 15 years since he left. I ’ ll tell him the news as soon as I see him. Once you have got used to it, you will like it. I waited till he had finished his work. 注意: (1) when, as, while 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) 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. as 也可表示“随着”,但要注意与 with 的区别: ? As the day went on , the weather got even cold.( 从句, 故用谓语动词) ? With the day going on , the weather got even cold.( 介词, 故用非谓语) 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 position.