in which此处为何不可用where代替?

问题描述:

in which此处为何不可用where代替?
The ladder on which I was standing began to slip.为何不能用where来替代

这里 The ladder began to slip 是整个句子的主干,which作为 stand on的宾语,整个句意为我正站着的*开始滑落,where 引导的定语从句先行词应为地点,ladder 并不能表明地点,如非要替换句意就为我站的*那块开始滑...