Complex sentence: Roberto Clemente Walker (August 18,1934--December 31,1972) was a Puerto Rican baseball right fielder who played 18 seasons in Major League Baseball (MLB) for the Pittsburgh Pirates from 1955 through 1972.
Split into simpler sentences: Roberto Clemente Walker (August 18,1934--December 31,1972) was a Puerto Rican professional baseball player. He was a Major League Baseball (MLB) right fielder who played 18 seasons for the Pittsburgh Pirates from 1955 through 1972.