Write a famous saying of Confucius and annotate it.

Never tire of learning and never tire of teaching.

Confucius was famous for his eagerness to learn and showed great interest in all kinds of knowledge, so he was versatile and knowledgeable. He was very famous at that time, and was almost regarded as an omniscient saint, but Confucius himself didn't think so. Confucius said, "A saint cannot learn, but never tires of teaching." Confucius learned that there was no teacher. Whoever has knowledge and who doesn't understand will worship him as a teacher. So he said, "A threesome must have a teacher."

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