Question

英语问题：讲解句子结构

They are the principles on which my wife and i have tried to bring up our family. they are the principles in which my father believed and by which he governed his life. they are the principles,many of them,which i learned at my mother's knee.
i believe in the supreme worth of the individual and in his right to life, liberty, and the pursuit of happiness.
请高手给我讲解一下这段话，不理解，里面有on which,in which,by which.看不懂，谢谢！下面的也不理解，都弄不明白句子的结构。

Answer 1

都是宾语从句啊！！一个个分析吧：
on which那句理解成： my wife and i have tried to bring up our family on the principles

in which那句： my father believed in the principle

by which那句：he governed his life by the principles

最后是：i learned the principles at my mother‘s knee

追问

先感谢你的讲解，还有些问题：什么情况下用on which,什么情况下用in which,什么情况下用by which.有什么规定或技巧吗？我不知道为什么要这样用，第一句话是不是也可以用by which?

追答

不是啊，它是根据从句决定！就是怎么搭配的问题了。
像第二句，believe in，这是固定搭配，不可以用其他！第三句，govern……by……，也是一样！