sit down Emma . You will only make yourself more tired on your feet.A. to keepB. keeping

问题补充：

sit down, Emma . You will only make yourself more tired, on your feet.

A. to keep

B. keeping

C. having kept

D. to have kept

答案：

A. to keep

(答案→)B. keeping

C. having kept

D. to have kept

解析：

这题考查现在分词做条件状语的用法，句意是：坐下，Emma，一直站着的话，你只会让自己更累。选B。