The country has been war with its neighbor for almost ten years.A. inB. onC. atD. during

问题补充：

The country has been war with its neighbor for almost ten years.

A. in

B. on

C. at

D. during

答案：

A. in

B. on

(答案→)C. at

D. during

解析：句意：这个国家和邻国交战有近了。词组：be at war“处于战争状态； 在交战中”，

其他介词不能和war构成固定短语，选C。