Look! The boys football under the tree.A. playB. is playC. is playingD. are playing

问题补充：

Look! The boys football under the tree.

A. play

B. is play

C. is playing

D. are playing

答案：

A. play

B. is play

C. is playing

(答案→)D. are playing

解析：根据look 而知，说明本句子的时态为现在进行时，其结构为主语+be+doing sth 故在CD之间进行选择，而主语the boys 为复数形式，故选D