Prices may be subject to alteration.
价格可能会受变更影响。
There's even a special subject index.
甚至有一个特别的主题索引。
I'm doing some research on the subject.
我正就这一课题进行研究。
He is an engrossing subject for a book.
他是非常有趣的写书题材。
The books are grouped together by subject.
这些书按科目分类。