—— 请按键盘 空白键 开始游戏 ——

过去总是紧张的,未来是完美的。
The past is always tense, the future perfect.
"Nature never did betray the heart that loved her."
每一块石头,每一棵树,每一条河流都有一个故事要讲。
The challenge in model checking is not just to find errors, but to understand why they occur.