All who joy would win must share it. Happiness was born a twin.
学习数学的最好方法就是做数学。
经济学的未来在于弥合理论与实践之间的差距。
自然界的普遍法则大多不是直接感知的对象。
You don’t build a business—you build people—and then people build the business.
The war on coal is a war on the American worker.