Complex sentence: Petre began studying for the priesthood in 1872, was ordained in 1874 and taught for a few years at Downside Abbey where he endowed a library (from which the works of Charles Dickens were banned) a cloister and a swimming pool.
Split into simpler sentences: Petre began studying for the priesthood in 1872, was ordained in 1874, and taught for several years at Downside Abbey. During his time there, Petre endowed the school with a library (from which the works of Charles Dickens were banned) a cloister and a swimming pool.