九霄云外

jiǔ xiāo yún wài

(forgotten) completely; far, far away

Character by character

九jiǔ
nine

霄xiāo
heavens

云yún
clouds

外wài
beyond

一玩起游戏，他就把作业忘到九霄云外了。

Once he starts gaming, homework goes clean out of his head.

Tone: neutral.

Usually 忘到／抛到九霄云外.

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