Complex sentence: The Choir of St George's Chapel at Windsor Castle has been in existence since 1348 and, with the exception of the Commonwealth period (1649-1660), has sung services in the Chapel continuously ever since.
Split into simpler sentences: The Choir of St George's Chapel at Windsor Castle exists to sing services in St George's Chapel at Windsor Castle. It has been in existence since 1348 and, with the exception of the Commonwealth period (1649-1660), has sung services in the Chapel continuously ever since.