Complex sentence: The Jesuit University System (SUJ) is a network of private universities that belong to the Mexican Province of the Society of Jesus, which has universities around the world joined by associations such as the SUBJ.
Split into simpler sentences: The Jesuit University System (SUJ) is a network of private universities that belong to the Mexican Province of the Society of Jesus. The Society of Jesus has universities around the world joined by associations such as the SUBJ.