一本书是作者和读者之间的对话，一种超越时间和空间的对话。
"Un libro es una conversación entre el autor y el lector, un diálogo que trasciende el tiempo y el espacio."
I’m not good at being a hero, but I’ll try if it means I get to be your man.
Mathematics is not a spectator sport; to understand it, one must engage with it actively.
在商业和生活中，诚信是我们所做一切的基础。
The man with a toothache thinks everyone happy whose teeth are sound. The poverty-stricken man makes the same mistake about the rich.