The greatest problem for mathematicians now is probably the Riemann Hypothesis.
学者学习古人,开始时接触到的是粗浅的内容,中期接触到精华,最终领悟到其神妙变化。
La verdadera patria del poeta es su lengua.
The most advanced technology is worthless if farmers don't understand how to use it effectively.
The dialogue between old and new is what gives a city its richness.