25. Whenever I go to Beijing is quite frequent I will go to visit the Great Wall.A. whe

问题补充：

25. Whenever I go to Beijing, is quite frequent, I will go to visit the Great Wall.

A. where

B. which

C. as it

D. It

答案：

A. where

(答案→)B. which

C. as it

D. It

解析：根据句子结构可知，非限制性定语从句说明前面的事情，故答案选B。