守口如瓶

shǒu kǒu rú píng

to keep your lips sealed

Character by character

守shǒu
guard

口kǒu
mouth

如rú
like

瓶píng
bottle

关于新产品，公司上下守口如瓶。

The whole company is keeping tight-lipped about the new product.

Tone: positive (praise).

Praise for keeping a secret. Opposite: 口无遮拦 (blurting everything out).

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