下列哪一种现象的描述能说明分子在不停地运动( )
A:沙尘漫天
B:花香四溢
C:落叶纷飞
D:瑞雪飘飘
“人有悲欢离合,亦有喜怒哀乐。虽乃人之常情,却可有控而发。”这说明人的情绪( )
—________ is that man?
— You don't know him? He is Ma Yun.