The most important political challenge of our time is to create strong, effective, and accountable states.

酸的强度由其提供质子的能力来衡量，碱的强度由其接受质子的能力来衡量。

"The human condition is one of perpetual dissatisfaction; we are always searching for something more."

法律体系的存在是一个事实问题，而不是道德问题。