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.
What we learn from history is that people don't learn from history.
惩罚时不避忌权贵，奖赏时不遗忘地位低下的人。
The smell of freshly baked bread is the universal language of comfort.
找到平静的唯一方法是与自己和解。
如果我们让过去和现在争吵,我们将失去未来。
设计不是强加你的意志，而是发现已经存在的东西。