1. If you learn without thinking, you will be in vain; if you think without learning, you will be in danger. 2. If you review the past and learn the new, you can become a teacher. 3. Smart and eager to learn, and not ashamed to ask questions. 4. If I don’t know it well, if I don’t tire of learning, if I don’t tire of teaching others, what does that mean to me? 5. If you are a person of three, you must have a teacher; choose the good ones and follow them, and change the bad ones.