Kevin was not good at Chinese at first. After two months in China he made great progres

问题补充：

Kevin was not good at Chinese at first. After two months in China, , he made great progress.

A. while

B. but

C. however

D. otherwise

答案：

A. while

B. but

(答案→)C. however

D. otherwise

解析：副词辨析。A当…时；然而；尽管；B但是（后面不需要使用逗号）；C然而（前后都需要逗号隔开）；D否则，要不然；句意：Kevin起初不擅长中文，然而，在中国两个月以后，他取得了很大的进步。故C正确。