时间状语从句的时态问题●﹏●

Question

跪求使用when、while、 before、after 、as soon as、until 的具体时态，网上的看不懂，感谢高手解决疑难，最好准确一点，有例句。谢谢^_^

Answer 1

1.when后可用一般现在时,现在进行时,一般过去时,过去进行时.例:(1.)She often sits beside her daughter when she plays the piano.(2.)She is cooking when her daughter is playing the piano.(3.)When the alien landed,she was shopping.(4.)When she was shopping , the alien landed.
2.while后可用现在进行时或过去进行时。例：（1.) I always listen to the radio while I'm cooking.(2.)The accident happened while she was crossing the road.
3.before/after后可跟一般现在时或一般过去时。例：(1.)She often makes up before she leaves.(2.) His mother died after he sat the test.
4. as soon as 后可跟一般现在时或一般过去时。例:(1.)The girl begins to eat something as soon as she gets home.(2.)He would help his father sell fruits as soon as he left his school.
5.until 也只用于一般现在时或一般过去时中。例：(1.)I always don't eat meals until my parents begin to eat.(2.)I didn't know the news until he told me.

Answer 2

解析如下，仅供参考：
时间状语从句：用表示时间的连词连接一个句子作状语。
连接时间状语从句的连接词有：when, before, after, while, as soon as, until, since
如果主句是一般将来时，从句只能用一般现在时表示将来意义。

例句如下：
1. 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：
时间状语从句： When she came in, I stopped eating.她进来时，我停止吃饭。(瞬时动词)
　　 When I lived in the countryside, I used to carry some water for him.
当我住在农村时，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。
2. 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。（比）
3. It will be four days before they come back.
4. since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。一般情况下，从句谓语动词用一般过去时，而主句的谓语动词用现在完成时。但在It is +时间+since从句的句型中，主句多用一般过去式。例如：
I have been in Beijing since you left. 自从你离开以来，我一直在北京了。
It is four years since my sister lived in Beijing. 我妹妹不在北京住有四年了。
5. After we had finished the work, we went home.完成工作之后，我们回家了。
（从句用过去完成时，主句用一般过去时）
6. As soon as I reach Canada, I will ring you up. 我一到加拿大，就给你来电话。
7. I didn't go to bed until（till） my father came back.直到我父亲回来我才上床睡觉。本回答被网友采纳