We had an anxious couple of weeks for the results of the experiment.A. waitB. to be waiti

问题补充：

We had an anxious couple of weeks for the results of the experiment.

A. wait

B. to be waiting

C. waited

D. waiting

答案：

A. wait

B. to be waiting

C. waited

(答案→)D. waiting

解析：由于是主语等待，表主动，且在题干中充当方式状语。动词不定式不做方式状语。