Complex sentence: His uncle Georges Paulin was a part-time automobile designer and invented the mechanical retractible hardtop, who was later executed by the Nazis in 1941 as a hero of the French Resistance.
Split into simpler sentences: His uncle Georges Paulin was a part-time automobile designer and invented the mechanical retractible hardtop. He was later executed by the Nazi's in 1941 as a hero of the French Resistance.