人的自由是他的限制。
Man's freedom is his limitation.
理论地理学是空间科学的女王。
可持续性不是一个流行词,而是现代能源行业的商业必需。
There is only one good, which is knowledge, and one evil, which is ignorance.
发现的喜悦无疑是人类心灵所能感受到的最活跃的。