1. When three people are together, there must be my teacher.

It means that if there are many people together, there must be my teacher among them.

2. If you know something, you know it, and if you don’t know it, you don’t know it.

It means that if you know something, you know it, and if you don’t know it, you don’t know it (you can’t pretend to understand).

3. Be tireless in learning and tireless in teaching

It means to study hard without feeling bored and to teach others without feeling bored.