问题补充：
请高手帮忙分析一下这个句子中“to which”的用法He was a window into the extent to which our memories make us who we are.通过他,我们能了解到记忆在何种程度上塑造了我们的人格.看翻译很清楚,看句子很抽象.求分析
答案：
the extent to which 系英文惯用语,表达”到什么程度“,通常用作宾语从句,比如：We want to understand the extent to which smoking is related to lung cancer.
但在这句话里,它的作用是介词短语,修饰表语window.
======以下答案可供参考======
供参考答案1:
分开来理解，which指代事情，塑造了我们的人格这个事实。
例如下面两个句子
One thing I have never understood about Chinese parents is the extent to which they will neglect this. which指代他们对此事忽视
对于中国的父母们，我从来就理解不了的一点是他们对此事忽视的程度。
But we seldom realise the extent to which maths has invaded every corner of ourlives.
但是，我们很少意识到到的是数学是入侵我们生活的每个角落的程度。
extent to短语表示在。。程度上
