长难句分析Tounderstandthewidthanddepthtowhichsciencecanbeappliedtothematerialandspiritualproblemsthatconfrontindividualsandnationsrequiresanunderstandingofwhatsciencereallyis.参考译文：要了解科学可以在

Question

长难句分析
To understand the width and depth to which science can be applied to the material and spiritual problems that confront individuals and nations requires an understanding of what science really is.
参考译文：要了解科学可以在多大的广度和深度上解决个人所面临的物质和精神方面的问题,就需要了解科学究竟是什么.
疑问如下：) 在该句话中“to which”引导定语从句是修饰"the width and depth",但是我不明白“which”前的“to“从何而来,我猜测本来的顺序应该是to the width and depth,仅是根据语法结构进行猜测的.the width anddepth作为先行词在从句中又是做什么成分呢?Science can be applied to the material and spiritual problems that ...to the width and the depth.
能不能帮忙分析一下句子结构 在从句中做什么成分呢？

Answer 1

to which=to the width and depth,应该是这样
为了了解深度和广度,什么样的深度和广度呢? 科学应用于物质和精神方面的问题的深度和广度. to the width and depth作状语