I think it's time to hit the books.

我想是时候看书了。

A student might have to tell her friends she cannot go with them to the movies because she has to hit the books.

一个学生或许会告诉朋友，她不能跟他们一起去看电影，因为她要学习。

When a student's grades hit bottom it is time to hit the books. Hit the books is another way to saying it is time to study.

当学生成绩不好时，那就到了hit the books的时候了。Hit the books是表示到了学习时候的另一个表达。