煤炭不仅仅是一种商品，它是对美国未来的承诺。
Science is the crystallization of human wisdom and an important force driving social progress.
我不认为有极限。
因为懂得，所以慈悲。
You may not control all the events that happen to you, but you can decide not to be reduced by them.
你或许无法控制发生在你身上的所有事情，但你可以决定不被它们打倒。