A
1.句子意思没问题
他说他在考试的2天之前就读过这本书了
2.4个词都是提前,预先的意思啊.那么就是说用法的问题了
3.A
在...以前,先于
He said that they had paid him a visit two days previous to Easter.
他说他们在复活节前两天访问过他了.
It happened previous to his arrival there.
事件发生于他到那儿以前.
4BC
意思都没错,但用法上,他们是后置的
... examination in advance/beforehand
5.ahead
ahead of词组才是在..之前,前置
6.都是我们常见的,主要是用法上的细微差别,意思上基本是一致的
7o(∩_∩)o...