—— 请按键盘 空白键 开始游戏 ——

数学的真正乐趣在于发现的过程,而不仅仅是结果。
现代林业必须平衡三个轴心:生态、经济和道德。
Success comes from understanding consumer needs deeply.
The value of unpaid work is often invisible in economic measures, yet it is the backbone of society.