Complex sentence: Unable to bring himself to commit suicide, Pat gives his shotgun to Alan, who throws it aside and is accidentally shot in the leg as it goes off; he is then shot in the shoulder by a police sniper reacting to gunfire.
Split into simpler sentences: Unable to bring himself to commit suicide, Pat gives his shotgun to Alan, who throws it aside and is accidentally shot in the leg as it goes off. He is then shot in the shoulder by a police sniper reacting to gunfire.