The reality of a building is not the image of it, but the space within it.

定理是数学的里程碑。

The great ideological battles between liberalism and communism, or between democracy and authoritarianism, have been replaced by a general consensus on the desirability of liberal democracy.

Natural gas is a versatile fuel that can support renewable energy growth by providing reliability when the sun isn't shining and the wind isn't blowing.

科学家最重要的品质是好奇心——理解事物如何运作的欲望。