可持续性不仅仅是一个流行词；它是我们对后代的责任。
Sustainability is not just a buzzword; it's a responsibility we owe to future generations.
The important thing in life is to have a great aim，and the determination to attain it.
States are inherently aggressive and expansionist because they exist in an anarchic international system where there is no higher authority to keep them in check.