你这个问题以前已经讨论过，为此我还一不小心引爆了这里的一辆粪车，呵呵。

总体把握两点

（1）

from where 来自from there

from which 来自 from sth (比如it)

where的惯用

（2）

追究原始句

### 这是个很大的话题，但搞好上面两点，也就化繁为简了。

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They returned to the point where they had started from. =

1. They returned to the point.  2.  they had started from there. 

They returned to the point which they had started from. =

1. They returned to the point.  2.  they had started from the place. 

(以上point是都指“地点”)

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以后遇到from where在大多数情况下，理解成from which就可以了？

结论是：不一定

仅举几个例子：

1a. I stood on the desk and saw the cow.

1b. I stood on the desk and saw the pencil.

from which

I stood on the desk, from which I saw the cow.

I stood on the desk, from which I saw the pencil.

I stood on the desk, on which I saw the cow. (X，因为太奇怪了)

I stood on the desk, on which I saw the pencil. (只会理解为pencil与“I” 都在桌子上)

上面的例子，想想它们的原始语句，自然就明白：

I stood on the desk；I saw the cow / the pencil from it.

from where

I stood on the desk, from where I saw the cow.

I stood on the desk, from where I saw the pencil.

"I"在桌子上， cow和pencil在离桌子有些距离的地方

原始语句：

I stood on the desk；I saw the cow / the pencil from there.

(这里用from there比较别扭，可能句子本身别扭，也可能the desk 面积有限，太具体。如不用desk, from there的结构就让人就觉得蛮舒服；也就是，这不是from where本身有什么语法问题。其它场合from where也许就不会有问题)

where

I stood on the desk, where I saw the cow. 

I stood on the desk, where I saw the pencil.

原始语句：

I stood on the desk；I saw the cow / the pencil there. (这句的there得依所见目标而定“在哪里”)

的确，

where= in which, on which, at which...等等

抽掉前半句，只看后面：

where I saw the cow.

where I saw the pencil.

咋一眼，“在那里where”似乎就是在身边<-----自己在事件发生地

但一旦加上前半句，语义超乎语法的作用就显现出来了：

I stood on the desk, where I saw the cow. 

where= from which <--------变成了“观察视角”

I stood on the desk, where I saw the pencil.

这个句子不好，where不确定, 它到底是on which 还是from which?

我看过哈代这种where用法，高中有篇讲火山的课文，也有这种where

可惜这两种书，现在我身边都没有，不能提供这两个原始例句。