Complex sentence: Isabel de Verdun, Lady Ferrers of Groby (21 March 1317--25 July 1349) was an English heiress, and the eldest daughter of Elizabeth de Clare, and through her, the great-granddaughter of King Edward I of England.
Split into simpler sentences: Isabel de Verdun, Lady Ferrers of Groby (21 March 1317--25 July 1349) was an heiress and a member of the English Royal Family. Isabel was the eldest daughter of Elizabeth de Clare, and through her, the great-granddaughter of King Edward I of England.