每一条边界都是虚构的，先在脑海中划定，然后才在大地上留下伤痕。
"Every border is a fiction, drawn first in the mind before it scars the earth."
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。
Financial stability is the cornerstone of economic stability.
A society’s competitive advantage will come not from how well its schools teach the multiplication and periodic tables， but from how well they stimulate imagination and creativity.