Complex sentence: The renewal of the Constantinian basilica of St. Peter was assigned to Bernardo Rossellino and provided for the continuation of the body by covering it with five aisles and longitudinal cross vaults on pillars that were to incorporate the old columns.
Split into simpler sentences: The renewal of the Constantinian basilica of St. Peter was assigned to Bernardo Rossellino. The body was expanded with five aisles and longitudinal cross vaults on pillars that were to incorporate the old columns.