废寝忘食

fèi qǐn wàng shí

so absorbed that you forget to eat and sleep

Character by character

废fèi
neglect

寝qǐn
sleep

忘wàng
forget

食shí
food

他废寝忘食地准备考试。

He prepared for the exam so hard he forgot to eat and sleep.

Tone: positive (praise).

Echoes Confucius's self-portrait 发愤忘食 in the Analects; mostly praises devotion to study or work.

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