A:has been designed
B:had been designed
C:was designed
D:would be designed
阅读《望天门山》写出诗句的意思,然后完成填空练习。
望天门山
天门中断楚江开,
碧水东流至此回。
两岸青山相对出,
孤帆一片日边来。
做匀速圆周运动的物体( )