–Do you still remember the city we visited last year ?--You mean Zhengzhou? I know there

问题补充：

–Do you still remember the city we visited last year ?

--You mean Zhengzhou? I know there is a factory your mother worked.

A. that, which

B. where, that

C. which, where

D. where, where

答案：

A. that, which

B. where, that

(答案→)C. which, where

D. where, where

解析：句意：你还记得我们去年参观过的那个城市吗？你的意思是郑州？我知道你妈妈在那里的一个工厂工作过。第一空中which 引导定语从句在句中作为宾语，第二空定语从句中不缺主语和宾语，用where作为地点状语，故选C