我不考虑年龄。如果你继续努力工作，你可以继续前进。
I don’t think about age. If you keep working hard, you can keep going.
The state, therefore, has not existed from all eternity. There have been societies that did without it, that had no notion of the state or state power. At a certain stage of economic development, which was necessarily bound up with the split of society into classes, the state became a necessity.
We can’t ignore the economic role of coal, but we also can’t ignore its environmental impact.
好的插画不只是装饰文字，而是扩展它。
The pursuit of mathematical truth is a pursuit of beauty, elegance, and simplicity.
你知道的越多，你就越意识到你不知道的越多。