反馈是一个强大的概念，在自然系统和技术系统中被广泛使用。

A people without children would face a hopeless future; a country without trees would face a future with even less hope.

Never underestimate the power of a motivated team. They can achieve the impossible.

Intelligence plus character – that is the goal of real education

生活的真相很简单，但我们讲述的故事却非常复杂。