A：始终静止不动
B：动了一点点，很快停下来
C：撞击时开始运动，然后慢慢停下来
D：撞击时开始运动，然后做匀速直线运动
Cindy _______ rice for breakfast.
世界各大洲中，高低起伏最大的洲是（ ）
It is very dangerous children to cross the busy street.
— ________ does it take Bob to get to his grandparents' home?
— An hour.
