The simplest drawings can often carry the deepest emotions.

动态规划理论基于最优性原理，该原理指出，无论初始状态和初始决策如何，剩余决策必须构成关于第一个决策所导致状态的最优策略。

The historian must be impartial, but not indifferent.

I'm not a girl who hides her light. I'm a girl who shines.

Man is so much the voice of his interest that it is not enough to make him see the right， but you must make him feel it.

林业的未来在于平衡经济增长与生态保护。