Complex sentence: As Bodley and Garner's commissions increased, they became less exclusively ecclesiastical, and though church building remained predominant, their practice widened to collegiate buildings in Oxford and Cambridge, and to private houses and offices.
Split into simpler sentences: As Bodley and Garner's commissions increased they became less exclusively ecclesiastical. Church building remained predominant but their practice widened to collegiate buildings in Oxford and Cambridge, and to private houses and offices.