when和which的用法？

Question

如题所述

Answer 1

when可作疑问副词，也可作连接词引导多种从句，在多项语法中都有涉及，也是高考的重点。下文是对when用法的总结。
1.引导特殊疑问句，可译为“什么时候”When do you think the patient can be operated on？2.可引导不定式短语做主语或宾语Ask him when to open the red wine.3.可引导限定性和非限定性定语从句，修饰主句中表时间的先行词，并在从句中做状语。
There will be one day when the impossible today may become possible.(限定性定语从句)
We will put off the picnic until next week，when the weather maybe better.(非限定性定语从句)
4.引导名词性从句
1)引导主语从句
When the foreign friends will arrive is not known yet.
2)引导宾语从句Lily is asking when she can go back to her hometown again.
3)引导表语从句That was when I was thirteen.
4)引导同位语从句Can you answer the question when Penicillin was discovered？
注意：when引导的主语从句有时会用形式主语it代替When the foreign friends will arrive is not known yet.=It is not known yet when the foreign friends will arrive.
5.引导时间状语从句，可译为“当…时候”，本文开始课文句子中的when即为此用法。
When he got up，he felt dizzy.
6.when引导从句的特例：
1)表示突然发生某事或紧接着发生某事，常可译为“…还没/刚刚…就…”，“…正在…忽然…”或“正要…这时…”，主要用于“had done…when…，be doing…when…和be about to do…when…”这三个句式I had hardly opened the door when the man hit me.
2)表示对比，常可译为“本该/本可以…却…”Why are you here when you should be at school？
3)表示让步，常可译为“既然”或“在…情况下”
How can they learn anything when they spend all their time watching TV？

Answer 2

when问的是时间..
which问的是哪一个东西..