质量不是成本；它是一种投资。

Words were not given to man in order to conceal his thoughts.

学习数学的最好方法就是去做数学。

When we think we have been understood, we feel we can control the world around us.

Love is the world's infinite mutability; lies, hatred, murder even, are all knit up in it.

可持续发展不再是可选项；它是任何希望在未来蓬勃发展的企业的必需品。