When I came back yesterday evening my brother his homeworkA is doing B. has done C. w

问题补充：

When I came back yesterday evening, my brother his homework.

A is doing B. has done C. was doing

答案：

解析：时态的用法。句意：当我昨天晚上到的时候，我的哥哥/弟弟正在做家庭作业。根据句意，应该用过去进行时，故答案为C。