The tragedy of great power politics is that even well-intentioned states are forced to act in ways that can lead to conflict and war.

水产养殖的未来在于循环水系统——它们将废物转化为机遇。

教育是你可以用来改变世界的最强大武器。

理论上，理论和实践之间没有区别。但实际上，是有区别的。