Complex sentence: Luitgarde of Vermandois (c.914--February 9,978) was a duchess consort of Normandy by her first marriage, and a countess consort of Blois by her second.
Split into simpler sentences: Luitgarde of Vermandois (-- February 9,978) was a French noblewoman. She was a countess of Vermandois by birth and a duchess consort of Normandy by her first marriage, and a countess consort of Blois by her second.