发现恒星围绕银河系中心的超大质量黑洞运行是天体物理学的一个转折点。

It is human nature to think wisely and act foolishly.

A company's culture is defined by the actions of its leaders, not just their words.

The balance between energy needs and environmental protection is the challenge of our time.

All that is in motion must be at peace； it is not what is at rest that should be considered peaceful.

伟人是公众的不幸。