Berean Study Bible
if only to teach warfare to the subsequent generations of Israel, especially to those who had not known it formerly:

King James Bible
Only that the generations of the children of Israel might know, to teach them war, at the least such as before knew nothing thereof;

American Standard Version
only that the generations of the children of Israel might know, to teach them war, at the least such as beforetime knew nothing thereof:

Darby Bible Translation
only that the generations of the children of Israel might know war by learning it, at the least those who before had known nothing thereof:

Douay-Rheims Bible
That afterwards their children might learn to fight with their enemies, and to be trained up to war:

English Revised Version
only that the generations of the children of Israel might know, to teach them war, at the least such as beforetime knew nothing thereof;

Young's Literal Translation
(only for the sake of the generations of the sons of Israel's knowing, to teach them war, only those who formerly have not known them) --