榆木脑袋

Explanation: Metaphor of a diehard. Also for the Elm skull. " 　　Source: Gu Yu, "the new new thing to do" your mother is not a dumb head! Zuojiao not get married, so do the net these days, I also agree. " 　　Examples: Uncle, Thank you for the elderly! "Gold and India tears on a drip, you knock on my neck Fengyun Elm child skull cavity." ★ Liu Shaotang "Liu umbrella" three