hit the books 
 
Literally, hit the books means to physically hit, punch or slap your reading books. However, this is a commonly used expression among students, especially American college students who have a lot of studying to do. It simply means “to study,” and is a way of telling your friends that you’re going to study.
从字面上看，hit the books的意思是用身体部位击打或拍打你正在阅读的书籍。然而，这个短语是一个学生常用的表达，尤其是美国的大学生，他们有很多的学习任务要完成。它的意思简单来说就是“学习”，是告诉你的朋友你要学习的一种表达。
 
It could be for a final exam, a midterm test or even an English exam.
可能是为了期末考试，期中考试，甚至是英语考试。
 
例：
Sorry but I can’t watch the game with you tonight, I have to hit the books. I have a huge exam next week!
对不起，我今晚不能和你一起看比赛了，我得用功读书了。下星期我有一个重要的考试。