Numbers 31:18

But all the women children, that have not known a man by lying with him, keep alive for yourselves.
— Numbers 31:18, King James Version

In other translations

World English Bible (WEB)

But all the girls, who have not known man by lying with him, keep alive for yourselves.

American Standard Version (ASV)

But all the women-children, that have not known man by lying with him, keep alive for yourselves.

Young's Literal Translation (YLT)

and all the infants among the women, who have not known the lying of a male, ye have kept alive for yourselves.