give the game away

動詞

慣用表現

(idiomatic) To mistakenly reveal a secret.

日本語の意味

うっかり秘密を漏らす / 誤って秘密を明かす

Don't give the game away by telling him about the surprise party.

彼にサプライズパーティーのことを話して、うっかり秘密を漏らさないでください。

意味（1）

(idiomatic) To mistakenly reveal a secret.

You don't want to mention the money involved; that would give the game away.