Mum may I watch TV for a while ? –of course if your work .A. is finishedB. finishesC. ha

问题补充：

Mum, may I watch TV for a while ? –of course, if your work .

A. is finished

B. finishes

C. have been finished

D. will be finished

答案：

(答案→)A. is finished

B. finishes

C. have been finished

D. will be finished

解析：句意：妈妈，我能看会电视吗？当然可以，如果你的作业完成了。句中主语work与动词finish是被动关系，要用被动语态；而且work 是不可数 名词，谓语动词只能用单数形式，故选A。