NET

2 He left those nations simply because he wanted to teach the subsequent generations of Israelites, who had not experienced the earlier battles, how to conduct holy war.

Darby

2 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:

KJV

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

Strong's

2 Only that^H7535 the generations^H1755 of the children^H1121 of Israel^H3478 might know^H3045, to teach^H3925 them war^H4421, at the least such as before^H6440 knew^H3045 nothing thereof;