通往可持续能源未来的道路需要一种平衡的方法，考虑经济、环境和社会因素。
The world is a mosaic of fleeting moments, each one precious in its own right.
Letters are the biographer's gold mine; they reveal what official records conceal.
气候变化是本世纪的战斗，我们必须赢得胜利。