Everyone is in favor of free speech. Hardly a day passes without its being extolled， but some people's idea of it is that they are free to say what they like， but if anyone else says anything back， that is an outrage.

理解基础是掌握任何复杂系统的关键。

The Langlands program is a reflection of the depth and beauty of mathematical thought.

安全环保是企业的生命线，任何时候都不能放松。