滴水不漏

dī shuǐ bù lòu

watertight; giving nothing away

Character by character

滴dī
drop

水shuǐ
water

不bù
not

漏lòu
leak

他的回答滴水不漏，记者什么也没问出来。

His answers were watertight; the reporters got nothing out of him.

Tone: neutral.

For airtight answers, plans or security; can hint at evasiveness.

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