—— 请按键盘 空白键 开始游戏 ——

The knowledge of the past stays with us to spur us on to new and better things.
Coal’s future depends on our ability to make it cleaner and more efficient.
可持续性不是一种趋势,而是生存的必需。
可持续农业需要在技术和生态保护之间取得平衡。