Mr. Smith a grammar book meant for senior high school students and will almost finish it.

问题补充：

Mr. Smith a grammar book meant for senior high school students and will almost finish it.

A. has been writing

B. has written

C. was writing

D. has been written

答案：

(答案→)A. has been writing

B. has written

C. was writing

D. has been written

解析：考察时态和语态。句意：史密斯先生一直在写一本为高中生使用的语法书，很快就要完成了。根据句意说明这本书还没有写完，在过去这段时间里他一直都在写。使用现在完成进行时表示从过去到现在的一段时间里一直在做的事情，故A正确。