里氏替换原则是面向对象编程中的一个基本概念，它指出子类的对象应该能够替换超类的对象而不影响程序的正确性。
The Liskov Substitution Principle is a fundamental concept in object-oriented programming, stating that objects of a superclass should be replaceable with objects of a subclass without affecting the correctness of the program.
痛苦并不总是身体上的；有时最深的伤口是我们看不见的。
The truth is not always beautiful, nor beautiful words the truth.
——日本人想控制上海，想尽一切办法、千方百计对杜月笙进行拉拢，杜月笙如是说。
我们都在互相陪伴着回家。
I don't make music for the charts, I make it for the people.