of which? of that?

Question

This is all the information "of which" I am aware.
請問"of which"為何不能用"of that"?

Answer 1

這一句原本的句型是
This is all the information which I am aware of.
而這句只是把介系詞移到關係代名詞前面
→This is all the information of which I am aware.

但如果關係代名詞前面有介系詞或逗點時
是不可用 that 做關係代名詞的
例：
The chair on which you are sitting is broken.
The book for which we are looking belongs to me.
Swimming, which is a good sport, makes people strong.
Mr.Wang has two houses, which are built of bricks.

所以這句只能用"of which"而不能用"of that"