It is so hard to believe because it is so hard to obey.
The writer must have the courage to say what others dare not say.
可持续发展不仅仅是一个流行词,而是我们对后代的责任。
Eyes deceive and legs fail, but it's the stomach that gets you in trouble!
数学和计算机科学的交叉点是一些最激动人心的发现产生的地方。