文化进化的研究必须考虑社会的内部动态和外部环境约束。
The world is a place of the living, and the dead have no place in it. The dead are nothing. They are not even a memory. They are forgotten.
通过文学，我们可以更好地理解他人和我们自己。
In the realm of computational learning, the key is not just to learn, but to learn efficiently.
