Complex sentence: In 1506 he laid the foundation stone of the new St. Peter's Basilica, and he was a friend and patron of Bramante and Raphael, and a patron of Michelangelo.
Split into simpler sentences: In 1506 he laid the foundation stone of the new St. Peter's Basilica. He was a friend and patron of Bramante and Raphael, and a patron of Michelangelo.