cat out of the bag

基本解释

Their engagement was to be a secret but the ring on her finger let the cat out of the bag.
他們倆訂婚原本想保密的，可是她手指上的戒指卻把這個秘密泄露出來了。
I will give my mother a surprise on her birthday, but my father let the cat out of the bag.
我本來想在媽媽過生日的時候給她一個驚喜，沒想到爸爸卻泄露了秘密。
Letting the cat out of the bag is supposed to stem from a trick played in old markets where buyers were duped when they thought they were buying a suckling pig.
一般認爲，“把貓從袋子裡放出來”的說法源自古代集市上的一個把戯：有時，商販會欺騙買家，在他們購買乳豬的袋子裡裝一衹貓。

Just be careful not to let the cat out of the bag, or someone may leave you holding the bag.
If you tell about something that was supposed to be a secret, we say you let the cat out of the bag.
The phrase to be left holding the bag is as widely used as the expression to let the cat out of the bag.

Construction and Housing Minister Ariel Attias let the cat out of the bag.
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