Impero, I command; imperial, emperor, empire.
Insula, an island; isle, insular, peninsula, insulate. [Island is not connected with this root. It was in older English spelled iland.]
Iter (itiner-is), a journey; itinerant.
Jacio (jact-um), I throw; adjective, project, injection.
Judex (judĭc-is); (adjudge), judicial.
Jungo (junct-um), I join; junction, conjoin, juncture.
Jus (jur-is), law, right; justice, jurisdiction, jury.
Labor (laps-us), I glide; lapse, collapse.
Lædo (læs-um), I injure; collision, lesion.
Lapis (lapĭd-is), a stone; lapidary.