Accustomed to the steep mountain he had no difficulty reaching the top.A. climbingB. cl

问题补充：

Accustomed to the steep mountain, he had no difficulty reaching the top.

A. climbing

B. climb

C. having climbed

D. have climbed

答案：

(答案→)A. climbing

B. climb

C. having climbed

D. have climbed

解析：固定句型become/be accustomed to doing sth.习惯于做某事。故选A. 这不选C或D。因为此处不存在先后关系一说，having done 一般非谓语动词连用，这里不能与宾语climbing连用。