Complex sentence: René Margotton was a French painter of School of Paris one of the last cubist of the 20th century, born in Roanne, France, in 1915 and died in 2009.
Split into simpler sentences: René Margotton was a French painter of the School of Paris, one of the last cubists of the 20th century. He was born in Roanne, France, in 1915, and died in 2009.