关于英语中的 非限制性定语从句he had committed a murder ,for which he got i

非限制性定语从句,可用which引导.
前边加个介词绝对可以,所加词需根据从句中搭配来定,就拿你举的例子来说,for which he got into trouble如果将which还原,可变成
he got into trouble for committing a murder
got into trouble for 可看成搭配
于是就有了诸如in which ,for which ,at which 等引导次的出现.
why 确实不能引导 非限制性定语从句,此处"="指两词意思相同,不过我觉得此处in which 和because意思相近
翻译:他犯了一企谋杀案,因此陷入麻烦.

hkfjdhgkfn

for which = why 只是意思一样，但是用法不同。是不冲突的。

for which中的for原来是在句末的。非限从句which前的介词原来位置都在句末的，只不过为了好看就提前了。正常语序就是He had committed a murde,which he got into trouble for.
同理，in which ,at which前的介词都应该在句末

for which 不等于why, 只是在某些情况下，例如：For which you want to see him? （为什么你一定要见他），而且这种互换只在口语里面。
从句当中，尤其是定语从句当中，因为which要充当关系单词，所以for which 只表示为“因为什么原因”。 例如：he had committed a murder, for which(murder) he go...