Complex sentence: Robert A. Sungenis (born 1955) is an American Catholic author of apologetic works critiquing the Protestant doctrines of "sola fide" and "sola scriptura".
Split into simpler sentences: Robert A. Sungenis (born 1955) is an American Catholic apologist. Sungenis is known for his apologetic works critiquing the Protestant doctrines of "sola fide" and "sola scriptura".