问题补充：
---Why can you speak English so fluently?
---Oh, I English in Shanghai International Studies University for four years.
A. studied
Bwould study
C. was studying
D. had studied
答案：
A. studied
B. would study
C. was studying
D. had studied
解析：乙英语之所以说得流利，是因为在上海国际关系学院读过四年。在上海读书是过去的事情，用一般过去时。本题干扰最强的是D项。had done表示“过去的过去”。本题不表示“过去某个时间之前”在上海读过四年。故答案为A.
