Complex sentence: As the small "horseless carriage" manufacturers became consolidated under the mantle of the General Motors Corporation, Pontiac grew as the industry grew, suffering the same setback as other cities during the Great Depression years of the 1930s.
Split into simpler sentences: As the small "horseless carriage" manufacturers became consolidated under the mantle of the General Motors Corporation, Pontiac grew as the industry grew. It also suffered the same setbacks as other cities during the Great Depression years of the 1930s.