"To be useful was the best thing the old men ever hoped for themselves, and to be aimless was their worst fear."
有用是这些老人曾经对自己最好的希望,而无目的是他们最深的恐惧。
煤炭的未来不在于数量,而在于我们能否清洁高效地利用它。
The world is not a puzzle to be solved, but a mystery to be lived.