The acid and base are complementary; one cannot exist without the other.
酸和碱是互补的；没有另一个，一个就无法存在。
求知若饥，虚心若愚。
When will you ever make me proud?
The task of the modern educator is not to cut down jungles, but to irrigate deserts.
如果我们让过去和现在争吵，我们将失去未来。