Complex sentence: The Legion become the official heroes of the newly formed United Planets and Superboy, handing over leadership of the Legion to Ultra Boy, renames himself Kal-El and starts dating Lois Olsen.
Split into simpler sentences: The Legion become the official heroes of the newly formed United Planets. Superboy handing over leadership of the Legion to Ultra Boy, renames himself Kal-El and starts dating Lois Olsen.