I became a student ten years. I have been a student 1996. I have studied here about 10 yea

问题补充：

I became a student ten years. I have been a student 1996. I have studied here about 10 years.

A. ago, since, for

B. ago ,for ,since,

C. ago, before, for

D. ago, in, after

答案：

(答案→)A. ago, since, for

B. ago ,for ,since,

C. ago, before, for

D. ago, in, after

解析：句意:十年前我成了一名学生。自从1996年我就是一名学生。我在这里学习已经了。ten years ago 十年前，ago 前用一段时间，表示一段时间以前；since 自从，后跟过去的时间，常跟现在完成时连用；for 后跟一段时间，表示一个动作持续了一段时间。故选A。