Complex sentence: He is sometimes listed as "Dr. Marion Tinsley" because he had a doctorate in mathematics and worked as a professor of mathematics in Tallahassee, Florida at Florida State University and at Florida A&M University.
Split into simpler sentences: He is sometimes listed as "Dr. Marion Tinsley" because he had a doctorate in mathematics. He worked as a professor of mathematics in Tallahassee, Florida at Florida State University and at Florida A&M University.