耳ěr濡rú目mù染rǎn

Literal: ears soaked, eyes dyed
Figurative: To absorb something without trying, from seeing and hearing it every day; unlike 潜移默化, it comes in through eyes and ears and is usually concrete, like a trade or a language.

Where does 耳濡目染 come from?

It does not come from a story: the image lies in the characters themselves. 濡 means "to soak" and 染 "to dye": what you hear soaks into your ears and what you see dyes your eyes, until you have made it your own without ever studying it. The idea already appears in an epitaph by Han Yu, the Tang-dynasty prose writer, who says the deceased learned this way, with no need for study, though with the order reversed: eyes first, then ears. Today it is mostly used for what you learn at home or from your surroundings, such as a trade, a language, or a hobby.

Source (出处): 韩愈《清河郡公房公墓碣铭》

How is 耳濡目染 used? Two examples

她tā爸bà妈mā都dōu是shì厨chú师shī，耳ěr濡rú目mù染rǎn，她tā从cóng小xiǎo就jiù会huì做zuò一yī桌zhuō好hǎo菜cài。
Both her parents are chefs, and from watching them she could cook a full spread when she was still a kid.
在zài上shàng海hǎi长zhǎng大dà的de孩hái子zi，耳ěr濡rú目mù染rǎn，多duō少shǎo都dōu能néng听tīng懂dǒng几jǐ句jù上shàng海hǎi话huà。
Kids who grow up in Shanghai hear Shanghainese all around them, so they can all understand at least a few phrases.

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