Complex sentence: Conditioned for racing by two trainers, Leo Azpurua, Jr and Terry J. Brennan at age two Certain in five starts had three wins and second twice his best winning proformance was in the grade three What a Pleasure Stakes.
Split into simpler sentences: Conditioned for racing by two trainers, Leo Azpurua Jr and Terry J. Brennan, Certain had three wins and two second places in five starts at age two. His best winning performance was in the grade three What a Pleasure Stakes.