—Shall we go out for a swim?—Sorry I can’t. I housework for my mother now.A. am doingB.

问题补充：

—Shall we go out for a swim?

—Sorry, I can’t. I housework for my mother now.

A. am doing

B. is doing

C. are doing

D. did

答案：

(答案→)A. am doing

B. is doing

C. are doing

D. did

解析：考查动词时态。根据语境“我不能出去游泳，（因为）我现在正在为我妈妈做家务。”后有now.故用现在进行时。选A。