Complex sentence: Derryl Cousins (born August 18,1946) is an umpire in Major League Baseball who has worked in the American League from 1979 to 1999, and throughout both major leagues since 2000.
Split into simpler sentences: Derryl Cousins (born August 18,1946) is an umpire in Major League Baseball (MLB). He worked in the American League (AL) from 1979 to 1999, and has umpired throughout both major leagues since 2000.