Silence is a virtue, but silence in front of someone you like is cowardice.

The comfort of the rich depends upon an abundant supply of the poor.

可持续性不仅仅是一个流行词；它是我们对后代的责任。

如果你不相信自己，别人也不会相信你。

数学的美在于它既精确又富有创造性。