Complex sentence: Walter Michael Miller, Jr. (January 23,1923 New Smyrna Beach, Florida--January 9,1996) was an American science fiction author primarily known for a single novel, "A Canticle for Leibowitz", the only novel he published in his lifetime.
Split into simpler sentences: Walter Michael Miller, Jr. (January 23,1923--January 9,1996) was an American science fiction author. Today he is primarily known for "A Canticle for Leibowitz", the only novel he published in his lifetime.