一个英语句子，关于从句的疑问词

这是一个特殊结构， 用 介词 + which + to 的不定式 起到一个定语从句的作用。其实整个句子可以改写成：

She was forever asking her parents for money with which she could buy new clothes.

with which 是不可以用词代替的，要改就改成句子。能够这样改还要有个条

件，就是 to do 的动作发出者必须和句子的主语一致。如：

I need a knife with which to cut the birthday cake.我要一把用来切生

日蛋糕的小刀。

相当于

I need a knife with which I can cut the birthday cake.

没有代替的词语，像上面那位说的那样可以去掉with which，
这里有个词组：buy sth with some money,是唯一的，不可替代，不要去想什么where了。。

forever应该是never吧？

可以去掉with which
直接用She was forever asking her parents for money to buy new clothes.

我觉得with which可去掉