Joan stood outside a shopping mall for a long time as if somebody.A. to wait forB. waiti

问题补充：

Joan stood outside a shopping mall for a long time, as if somebody.

A. to wait for

B. waiting for

C. waited for

D. having waited for

答案：

A. to wait for

(答案→)B. waiting for

C. waited for

D. having waited for

解析：考查非谓语动词。Joan和wait是主谓关系，用现在分词表主动和伴随状况，排除C；动词不定式表示目的，不符合语境，排除A；having done是现在分词的完成时，表示动作有先后，这里的stood和wait是同时发生的，排除D。waiting for相当于he was waiting for。故选B。