You can't please everyone, so don't try.
Mathematics is not just about numbers, equations, computations, or algorithms: it is about understanding.
Quality is not something you can add on to a product or service. It must be built in from the beginning.
生活对我们任何人来说都不容易。但那又怎样？我们必须有毅力，最重要的是对自己有信心。
In darkness, we learn to cherish the light.
You can't go back and change the beginning, but you can start where you are and change the ending.