☛He came back late because he had been waiting for her for two hours.

他回来得晚，因为他一直等了她两个小时。

☛He had been studying English for three years before he went abroad.

在他出国之前，他学习英语已三年了。

【跟踪典例】完成句子

①He came back at seven.He ________________ her for at least three hours.

他七点时回来的，他一直等了她至少三个小时。

②He ________________all before he went abroad.

在他出国之前，他学习英语已三年了。

③Nobody knew ________________ these days.

没人知道他们这些天一直在干什么。

④When I came in，he ________ his pen and he told me he had ________ for two hours.

我进来时，他正在找笔，他告诉我他已经找了两个小时了。

【答案】

2. Then as the article was going to be written in English Zhou Yang also took a copy to the native speaker

employed by the newspaper to polish the style.因为这篇文章要用英文来写，所以周阳拿了一份复印稿给一

位母语为英语的外国雇员来对语言风格进行润色。

as在此处引导的是原因状语从句，既可放在主句前也可放在主句后。一般来说，as引导原因状语从句表示双方都知道的原因。

☛As it's raining again，we'll have to stay at home.

因为又下起雨来了，我们只好待在家里了。

【拓展延伸】

as作连词引导状语从句的用法：

①引导原因状语从句，表示"因为；由于"。

☛As his mother was ill，he didn't come here yesterday.

因为妈妈病了，他昨天没来。

②引导时间状语从句，表示"一边......一边；当......时；随着......"。

☛She grew more beautiful as she grew older.

随着年龄的增长，她变得更漂亮了。

③引导方式状语从句，表示"正如，就像"。

☛He told us to do it as he did.

他告诉我们按照他所做的那样去做。

④引导让步状语从句，表示"虽然；尽管"，从句须用倒装程序。

☛Clever as he is，he can't work out this problem.

尽管他很聪明，他不可能算出这道习题。