Complex sentence: The Pratt & Whitney R4360 Wasp Major was a large radial piston aircraft engine designed and built during World War II. It was the culmination of its maker's piston engine technology, but the war was over before it could power airplanes into combat.
Split into simpler sentences: The Pratt & Whitney R4360 Wasp Major was a large radial piston aircraft engine. Designed and built by Pratt & Whitney during World War II, it was the culmination of their piston engine technology, but the war was over before it could power airplanes into combat.