A good book is often the best urn of a life enshrining the best that life could think out; for the world of a man’s life is,for the most part,but the world of his thoughts.
这是原句：其中,best urn后面的of a life是一个定语,修饰这个urn,而再后面的enshrining the best是一个现在分词短语,修饰urn,即这个urn包含了最好的,that life could think out这是一个定语从句,修饰前面的the best
一本好书常常是一个生命铭记其思想精髓最好的器皿；因为一个人的生命世界,有大部分,不过是其思想的世界.