|
2017年普通高考英语科语法知识网络 专题11 状语从句 When whenever When I came into the room, he was writing a letter.当我进屋时，他正在写信。 We shall go there whenever we are free.我们什么时间有空，我们就去那里。 when指的是“某一具体的时间” whenever指的是“在任何时间” when I was walking along the street when suddenly someone patted me on the shoulder from behind.我正在街上走着，这时忽然有人从后面拍我的肩膀。 when意为“这时”或“在那个时候”,可以看作是并列句,这种用法的when分句一般位于句末。 while While it was raining, they went out.天下雨的时候，他们出去了。 I stayed while he was away.他不在的时候我在。 while指“在某一段时间里”，“在…期间”，while引导的动作必须是持续性的 as He hurried home, looking behind as he went. 他赶快回家，不时地一边走一边向后看。 as引导持续性动作，强调主句和从句的动作同时发生 before Be a pupil before you become a teacher.先做学生，再做先生。 after He arrived after the game started.比赛开始后，他到了。 till We waited till (until)he came back .我们一直等到他回来。 如主句动词是持续性动作，常用肯定式，表示“直到…为止” | 
