题目内容：

英语翻译
Men often discover their affinity to each other by the love they have each for a book -------just as two persons sometimes discover a friend by the admiration which both have for a third.

优质解答

直译：人们(说明：men可以泛指人类)发现了彼此密切关系是因为靠他们对同一本书的喜爱,正如两人有时发现可以相互做朋友是因为他们共同对第三方（可是人/物）有钦佩之感.
意译：人类对同一本书的爱不释手因此发现彼此的相互联系,就如两人冥冥之中发现是朋友是因为二人是志同道合之人.
句子结构：
主句：Men often discover their affinity to each other by the love they have each for a book
men是主语,discover 是谓语,by介词,后面跟的是做方式状语
从句：just as two persons sometimes discover a friend by the admiration which both have for a third.
just as引导比较状语从句,后面的句子结构与主句是一样的.
two persons 主语,discover 是谓语,by介词,后面跟的是做方式状语.
一个句子可以有多个状语,但只能有一个谓语动词,除非有状语从句.
这是我的回答,纯手工,无机译,望采纳!