Chinese idiom:班门弄斧 During the Warring States period, there was a carpenter named Lu Ban. He was good at making woody tools.  One day, a young man passed by a red gate. He held up an axe with his hand and said: “This axe is really good. I can make the greatest tools in the world with it.” Hearing this, people around here all laughed. One person asked: “So, can you make a more beautiful gate than this one?” “That’s so easy! I was a student of Lu Ban before! Making a similar gate is like a piece of cake!” The young man said arrogantly. “But the gate was made by Lu Ban!” All people said. The young man was so embarrassed that he ran away immediately.