谁可以告诉我 when/as soon as/until/while 用这些次作时间状语从句的具体用法 特别是时态上的

when引导的从句的谓语动词可以是延续性的动词，又可以是瞬时动词。并且when有时表示“就在那时”。

例如：

When she came in, I stopped eating.她进来时，我在吃饭。(瞬时动词)

When I lived in the countryside, I used to carry some water for him.当的住在农村时，我常常为他担水。（延续性的动词）

We were about to leave when he came in.我们就要离开，就在那时他进来了。

While引导的从句的谓语动作必须是延续性的，并强调主句和从句的动作同时发生（或者相对应）。并且while有时还可以表示对比。例如：

While my wife was reading the newspaper, I was watching TV. (was reading是延续性的动词，was reading和was watching同时发生)

I like playing football while you like playing basketball.我喜欢踢足球，而你喜欢打篮球。（对比）

as soon as

as soon as 意义为“一…就” ，引导时间状语从句，可置于句首或句末，最常见的用法是在将来时态的情境中，遵守“主将从现”，的原则，i.e.

1. I'll write you as soon as I get there.

我一到那儿，就给你写信。

2. They will post the tickets to me as soon as they receive my cheque.

他们收到我的支票后就立刻把票寄给我.

3.Let us start as soon as he comes.

等他一来我们就动身。