—Have you handed in your schoolwork yet?—Yes I have.I guess it now.A. has gradedB. is gra

问题补充：

—Have you handed in your schoolwork yet?

—Yes,I have.I guess it now.

A. has graded

B. is graded

C. is being graded

D. is grading

答案：

A. has graded

B. is graded

(答案→)C. is being graded

D. is grading

解析：根据答句中时间状语now可判断出要用现在进行时,表示正在发生的事。又根据schoolwork与grade的关系可确定用被动语态,表示作业正在被批改，故选C项。一般现在时表示经常性的动作或存在的状态。选项A和D都不是被动语态,所以是错误的。