Complex sentence: Shelby Sumpter Singleton, Jr. (born Waskom, Texas, December 16,1931) is an American Music Producer and Record Label Owner who joined the Shreveport arm Mercury Records doing promotional work after he was injured the Marine Corps combat in Korea in 1958.
Split into simpler sentences: Shelby Sumpter Singleton, Jr. (born Waskom, Texas, December 16,1931) is an American music producer and record label owner. Born in Waskom, Texas, he joined the Shreveport arm Mercury Records doing promotional work after he was joined the Marine Corps and was injured in combat in Korea in 1958.