"In observational studies, we often have to rely on assumptions that are not directly testable."

我们讲述的故事塑造了我们生活的世界。

Music is the language that transcends all barriers.

不要为了得到世界而失去你的灵魂，智慧比金银更宝贵。

学习数学的唯一方法就是做数学。