the amount, level,or extent to which something happens or is present
这是新牛津对degree的讲解，请问which后面的是定语从句吗?请老师剖析一下!
是的，towhich…是定语从句，修饰前面的名词。the extend to which…意思是“在多大程度上”，这是一个常用表达。又如：
The extent to which your diet is successfuldepends on your willpower. 节食能有多大的效果取决于你的意志。
Languages vary in the extent to which they relyon word order. 语言对词序的依靠程度各不相同。
They experimented on the extent to which parents’ violence has aneffect on their children. 他们研究了爸爸妈妈的暴力会对孩子产生多大的影响。
They examined the extent to which age affectedlanguage-learning ability. 他们调查了年龄会在多大程度上影响语言学习力。
the amount to which, thelevel to which 的使用方法也类似。如：
the amount to which something is filled with people or things 密集程度（侧重从数目上考虑程度）
the level to which something is limited 某事物被限制和程度或范围
