--My father a letter yesterday, but I’m not sure if he has finished it.
---Why not ask him about it ?
A. wrote
B. was writing
C. has written
D. writes
网友回答
A. wrote
(答案→)B. was writing
C. has written
D. writes
解析：考查时态。句意：结合下文，我不确定他是否已经完成了。可知上文意思是，我的父亲昨天正在写一封信。描述过去正在进行的动作，用过去进行时态。故选B。