1. Teach an axe to teach others: Lu Ban, a native of Lu in the Spring and Autumn Period, was a famous carpenter. Dancing with an axe in front of Luban. Showing off one's skills in front of experts is a metaphor. {Example} I talk about operating experience in front of all the old masters, which is really ~ overreaching.

2. Throw an egg at a stone: throw an egg at a stone. Metaphor does not estimate their own strength, bring about my own destruction. From the Warring States Period, Xun Kuang's Xun Zi Yi Bing

3. The gladiator blocks the car with his arm: The gladiator overreaches himself in blocking the car with his arm, which means that he doesn't know if he is competent when he raises his arm against the car.

4. The tiger's head itches.

5. Play with a broadsword in front of Guan Gong.