Why not help when you were in trouble?A. you ask forB. ask forC. asking forD. asked for

问题补充：

Why not help when you were in trouble?

A. you ask for

B. ask for

C. asking for

D. asked for

答案：

A. you ask for

(答案→)B. ask for

C. asking for

D. asked for

解析：句意：当你有麻烦时，为什么去请求帮助？句式why not后接动词原形，用来提出某种建议，为何不做某事，故选B。