初中英语时间状语从句

a.表示“直到…,主句和从句都用肯定式?b.表示“直到……才”,主句用否定式,从? 句用肯定式。?例:They worked until it was late.? (他们一直工作到天黑。)? She didn't go to bed until she (had) finished her homework.? (她一直到写完作业才睡觉。)РsinceРsince引导的从句:表示“自从……以来“,从句中的动词一般表示动作的起点,用过去时。主句中的动词表示动作延续的情况,一般用现在完成时。如果主句中的动词表示的不是延续的动作而是表示目前的状态,可用一般现在时。?例:?Since he met this good friend, he has made great progress in his studies. (自从遇见了这个好朋友,他已在学习上取得了巨大的进步)?It is twenty years since she joined the Party.?(她入党二十年了。)(主句中的动词表示的不是延续动作,而是状态, 用现在时。)РasР由as引导的时间状语从句,[表示时间]当..., 的时候, 一边...一边, 随着。其从句的主语与主句的主语往往是同一人或物,?如:?1. She sang as she worked.?她一边工作一边唱歌。此句主从句还可使用进行时 She was singing as she was working.?2. I saw him as he was getting off the bus.?正当他下公共汽车时, 我看见了他。?3. As a child, he lived in America.?他小时候住在美国。?4. You will grow wiser as you grow older.?随着你年令的增长, 你会变得更聪明。