The Liskov Substitution Principle is a fundamental concept in object-oriented programming, ensuring that derived classes can be used in place of their base classes without altering the correctness of the program.

白云谦卑地站在天边，晨光给它披上壮丽的光彩。

"Hope is the thing that keeps us moving forward, even when the path is dark."

"The most important thing is to stay focused on the mission."

现代生活最深刻的问题源于个人在面对压倒性的社会力量、历史遗产、外部文化和生活技术时，要求保持其存在的自主性和个性。