数学不仅仅是关于数字、方程、计算或算法：它是关于理解的。

The beauty of a woman is not in a facial mode but the true beauty in a woman is reflected in her soul. It is the caring that she lovingly gives the passion that she shows. The beauty of a woman grows with the passing years.

What you actually pay for something is at least twice the listed price because of the energy， time， money needed to set it up， learn， maintain， repair， and dispose of at the end. Not all prices appear on labels. Actual costs are 2x listed prices.