Complex sentence: The Patriots' joined the 14--0 1972 Miami Dolphins, 11--0 1942 Chicago Bears, and 13--0 1934 Chicago Bears as the fourth team to record an undefeated season, also setting a record for most regular season wins in a single season.
Split into simpler sentences: The Patriots' joined the 14--0 1972 Miami Dolphins, 11--0 1942 Chicago Bears, and 13--0 1934 Chicago Bears as the fourth team to record an undefeated regular season. Their 16 wins also set a record for most regular season wins in a single season.