一个英语句子的问题Themostvaluablefindofallwastheship'slogbook,partsofwhichitwasstillpossibletoread.这是新概念3册第32课中的一句,partsofwhich后面为什么还要加it,我真的第一次看到这样的用法,

Question

一个英语句子的问题
The most valuable find of all was the ship's log book,parts of which it was still possible to read.
这是新概念3册第32课中的一句,parts of which 后面为什么还要加it,我真的第一次看到这样的用法,难道不能写成parts of which was still possible to read.

Answer 1

其实这句话可以理解为 it was still possible to read parts of which.parts of which是read的宾语,而it是形式主语.