精选优质文档-倾情为你奉上状语从句练习易混引导词while, when, as的区别:1.when既可以指时间点,与瞬间动词连用,也可以指时间段,与延续性动词连用(=while)。如:When he came in, his mother was cooking.When (While) we were at school, we went to the library every day.While表示时间段,因此,while 从句的谓语动词要用延续性动词。如:Please dont talk so loud while others are working.As与when用法相似,但着重强调主句动作与从句动作同时发生,有随着或一边一边之意。如:As you get older, you get more knowledge.随着年龄的增长,你获得的知识就越多。2Because,as,since 的区别:Because用于表示直接原因,回答why提出的问题,语气最强