Three fourth of the homework today .A. has finishedB. has been finishedC. have finishedD.

问题补充：

Three fourth of the homework today .

A. has finished

B. has been finished

C. have finished

D. have been finished

答案：

A. has finished

(答案→)B. has been finished

C. have finished

D. have been finished

解析：考查主谓一致和时态与语态。句意“今天作业的3/4已经被做完了。”homework是不可数名词，谓语用单数，排除C、D；homework和finish之间是被动关系，应该用被动语态。故选B。