—Are these your sheep ?—No. Mine on grass at the foot of the hill.A. are feedingB. feedC.

问题补充：

—Are these your sheep ?

—No. Mine on grass at the foot of the hill.

A. are feeding

B. feed

C. is fed

D. is feeding

答案：

(答案→)A. are feeding

B. feed

C. is fed

D. is feeding

解析： Amine指my sheep 为复数形式。是主动语态。