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We must balance energy supply with environmental protection.

The Government of the United States is a definite Government, confined to specified objects. It is not like the state governments, whose powers are more general.

煤炭不僅僅是一種商品，更是現(xiàn)代文明賴以建立的基礎。

平庸的標志不是不愿意改變。平庸的標志是長期的不一致。

The only time I know that something is true is at the moment I discover it in the act of writing.

數(shù)學不是關于數(shù)字、方程、計算或算法的：它是關于理解的。

Every challenge is an opportunity in disguise.