廢寢忘食

Simplified: 废寝忘食

On the HSK 7-9 vocabulary list, at CEFR level C2.

fèiqǐnwàngshí ㄈㄟˋ ㄑㄧㄣˇ ㄨㄤˋ ㄕˊ

    • to skip one's sleep and meals to be completely wrapped up in one's work

      idiom

Character by character

Sources