Complex sentence: Since then, Belichick has coached the Patriots to six Super Bowl appearances: victories in Super Bowls XXXVI, XXXVIII, XXXIX, and XLIX, and losses in Super Bowls XLII and XLVI.
Split into simpler sentences: Since then, Belichick has coached the Patriots to six Super Bowl appearances. His teams won Super Bowls XXXVI, XXXVIII, XXXIX, and XLIX and lost Super Bowls XLII and XLVI.