.The boy asked his parents to buy him a pair of binoculars which to watch football games.

问题补充：

.

The boy asked his parents to buy him a pair of binoculars which to watch football games.

A. in

B. through

C. from

D. on

答案：

A. in

(答案→)B. through

C. from

D. on

解析：考查介词辨析。句意“那个男孩让父母给他买一副双目镜，通过它，他可以看足球赛。”through“通过”。故选B。