Don't be childish any more.

别再孩子气啦。

youdao

Don't be childish. I'm just joking.

别孩子气了嘛，这只不过是开玩笑罢了。

youdao

Margo: I don't want to be childish, I'd settle for a few years.

玛歌：我不想要有孩子气，我的心早就平静好几年了。

youdao

To express any hope at this time they felt to be childish and stupid.

VOA: special.2010.03.06

That people playing a game should be childish: well, we associate being a child with playing games of course.

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In what could be considered a childish mindset, finding heroes in people I've never met, I'm taking great pleasure in reading about four new role models in a single week.

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It never ceases to amaze me to see how childish Wall Street can be sometimes.

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