The key is to set realistic customer expectations, and then not to just meet them, but to exceed them—preferably in unexpected and helpful ways.

数学的美在于它让我们看到世界上不立即显现的模式和结构。

I am made and remade continually. Different people draw different words from me.

热切而强烈的渴望，是一切有效努力的泉源。