It has yet to be proven that intelligence has any survival value.
The relationship between education and earnings is complex and varies across different contexts.
故事中最重要的不是发生了什么，而是为什么会发生。
The economics of gender is not a niche subject; it is central to understanding modern economies.
每起谋杀都有它自己的旋律。
Life is compared to a voyage.
《在北京五族共和合进会与西北协进会的演说》，1912年9月3日。