—— 请按键盘 空白键 开始游戏 ——

The past is always tense, the future perfect.
过去总是紧张的,未来是完美的。
A problem is in P if it can be solved quickly by a computer, and in NP if a solution can be verified quickly.
林业技术应该服务于自然,而不是征服它。
文学不是一场道德选美比赛。
A well-managed forest is a gift that keeps giving.