I walked slowly through the market where people all kinds of fruits and vegetables. I stu

问题补充：

I walked slowly through the market, where people all kinds of fruits and vegetables. I studied the prices carefully and bought what I needed.

A. sell

B. were selling

C. had sold

D. have sold

答案：

A. sell

(答案→)B. were selling

C. had sold

D. have sold

解析：句意：当我慢慢的走过市场时，那儿的人们正在卖各种各样的蔬菜和水果。

sell一般现在时表示经常性，习惯性的动作。had done过去完成时，表示过去之过去。having sold现在完成时，表示过去发生的动作对现在造成的影响。