法律的概念本质上是一个社会事实问题。
The concept of law is essentially a matter of social fact.
Mathematics is the foundation upon which all sciences are built.
People always feel happier when approaching happiness but become anxious when happiness is ongoing.
Innovation is the key to the continued growth and success of the Internet.
每一瓶饮料都在讲述一个故事，让你的故事值得讲述。