Complex sentence: The Catholic Church and many Protestant denominations, including Anglicans, Presbyterians, Lutherans and Methodists, celebrate the Feast of Christ the King on the Sunday before the first Sunday of Advent, the Sunday that falls between 20 and 26 November, inclusive.
Split into simpler sentences: The Catholic Church and many Protestant denominations, including Anglicans, Presbyterians, Lutherans and Methodists, celebrate the Feast of Christ the King on the Sunday before the first Sunday of Advent. The Feast of Christ the King is thus on the Sunday that falls between 20 and 26 November, inclusive.