关于两个定语从句同时修饰一个先行词的问题

关于两个定语从句同时修饰一个先行词的问题
请问,如果两个定语从句同时修饰一个先行词.
1）那么this is the book which I bought which I have lost和this is the book which I bought and which I have lost这两种写法都正确吗?
2）同样的,有这样一个句子：If the tradition of ambition is to have vitality,it must be widely shared;and it especially must be highly regarded by people who are themselves admired,the educated not least among them.
在这句话中,who are themselves admired以及the educated not least among them都是对people进行修饰,我知道原文表达的很清楚很地道,结构上也有美感.但是如果我想强行把后面一句改写成一个单一的两个定语从句修饰一个先行词的形式,我这样改合适吗：
It especially must be highly regarded by people,among whom the educated are not least,who are themselves admired.
OR
It especially must be highly regarded by people who are themselves admired and among whom the educated are not least
OR
It especially must be highly regarded by people who are themselves admired among whom the educated are not least
如果不合适而且您能肯定您的答案的话,能帮帮我写出一个合适的吗?