In international terms, an underage soldier is anyone recruited under the age of 18; a child soldier is under 15 years of age.

在国际条款中规定，任何未满18岁就被征召入伍的人就是未成年士兵。

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These retailers say they are aware of child-labor problems, have strict policies against selling products made by underage kids and abide by the laws of the countries from which they import.

FORBES: Magazine Article

Noting that 16 people refused to talk to investigators, many of them underage, DeWine said possible crimes to be investigated include failure to report a felony and failure to report child abuse.

NPR: Ohio Teens Guilty Of Rape, Face Year-Plus In Jail