The boy is waiting his sister and they will go to the hospital to wait their sick mother

问题补充：

The boy is waiting his sister and they will go to the hospital to wait their sick mother.

A. for,on

B. on,for

C. for,for

D. on.on

答案：

(答案→)A. for,on

B. on,for

C. for,for

D. on.on

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