Foolishly juvenile behavior or character; immaturity.

幼稚愚蠢的稚气的行为或性格；

youdao

Nelson's teacher was tired of his juvenile behavior and sent him to the principal for punishment.

纳尔逊的老师受够了他的幼稚行为，将他送给校长去处罚。

youdao

Feel free to call a company on behavior that is clueless, ridiculous, or whatever describes its behavior, but don't call individuals names. Name calling is juvenile and mean.

放心去说一个公司在行为上无能、可笑或其他一些可以形容它行为的描述，但是不要指称单个人的姓名，指名道姓是幼稚和低劣的。

youdao

Johnstone though is wary of legislation that could go about this the wrong way, criminalizing stupid, juvenile behavior or creating regulations that will be hard to enforce.

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"There is still a stigma associated with this pastime, " says Stefaan de Keersmaeker, a 41-year-old information-technology expert from Melbourne, who founded The Older Gamers because he "got fed up with all the juvenile behavior" from younger players online.

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