同一个圆内直径与半径的比是______：______．
通过圆的直径和半径的定义可知，直径：半径=2：1．
故答案为：2，1．
The players expected there ____ more free time before coming back to the country
From abroad.
A．is
B．being
C．have been
D．tobe
磨煤机灭火系统是怎样布置的？
