Complex sentence: Robert L. Johnson (born April 8,1946) is an American media magnate, the founder of television network Black Entertainment Television (BET), and its former chairman and chief executive officer.
Split into simpler sentences: Robert L. Johnson (born April 8,1946) is an American media magnate. He is best known for being the founder of television network Black Entertainment Television (BET), and is also its former chairman and chief executive officer.