—— 请按键盘 空白键 开始游戏 ——

理解的提高有两个目标:首先,我们自己的知识增长;其次,使我们能够将这些知识传递给他人。
The most important thing in mathematics is to understand the concepts, not just to memorize the formulas.
The art of being wise is the art of knowing what to overlook.