A:规律是客观的,不以人的意志为转移的
B:一切从实际出发
C:事物运动是有规律的
D:矛盾具有普遍性
It was ______ fine weather that they ________ went swimming.
一块橡皮的体积是6____.
一个卫生保健箱的体积是30____.
一堆钢材的体积是4____.