Is Jim in the gym by himself?No. There is another boy tennis with him.A. playingB

问题补充：

--- Is Jim in the gym by himself?

--- No. There is another boy tennis with him.

A. playing

B. play

C. plays

D. to play

答案：

(答案→)A. playing

B. play

C. plays

D. to play

解析：试题分析：句意：吉姆自己在体育馆吗？——不，有另一个男孩正在和他打网球呢。现在分词作补足语表示正在进行的伴随性动作，和句子主语是主谓关系。故选A。