空心圆轴和实心圆轴的外径相同时，截面的抗扭截面模量较大的是（）。

A.空心轴

B.实心轴

C.一样大

D.不能确定

—Did you have a______time______  in the park?

—Yes. I enjoyed myself very much.  [ ]

A. good;  playing    

B. nice; walk

C. pleasant; to walk    

D.  pleased; playing