Complex sentence: The H-body cars were replaced in the spring of 1981 with the new front-wheel drive J-cars which were designated as early 1982 models including, the Chevrolet Cavalier, Oldsmobile Firenza, Buick Skyhawk, and the Pontiac J2000.
Split into simpler sentences: The H-body cars were replaced in the spring of 1981 with the new front-wheel drive J-cars. Designated as early 1982 models they included the Chevrolet Cavalier, Oldsmobile Firenza, Buick Skyhawk, and the Pontiac J2000.