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.

中心地的规模和分布并非偶然，而是遵循一定的规律。

"The past is never dead. It's not even past."

我想像鸟儿歌唱一样作画。

我们不是环境的受害者，而是自己决定的产物。

The work of the philosopher consists in assembling reminders for a particular purpose.

Innovation in natural gas extraction is essential for meeting the world's growing energy demands.

文学是对抗狂热的最有效武器。