Complex sentence: Barry Nathaniel Malzberg (born 1939) is an American writer and editor, most often of science fiction and fantasy; initially in his post-graduate work he sought to establish himself as a playwright as well as prose-fiction writer.
Split into simpler sentences: Barry Nathaniel Malzberg (born 1939) is an American writer and editor, most often of science fiction and fantasy. Initially in his post-graduate work Malzberg sought to establish himself as a playwright as well as a prose-fiction writer.