NET
21 Their descendants remained in the land (the Israelites were unable to wipe them out completely). Solomon conscripted them for his work crews, and they continue in that role to this very day.
Darby
21 their children that were left after them in the land, whom the children of Israel were not able utterly to destroy, upon them did Solomon impose a tribute of bondservice until this day.
KJV
21 Their children that were left after them in the land, whom the children of Israel also were not able utterly to destroy, upon those did Solomon levy a tribute of bondservice unto this day.