Complex sentence: The Citroën Ami is a four-door, front-wheel drive supermini manufactured and marketed by Citroën from 1961 to 1978--at times the best-selling car model in France.
Split into simpler sentences: The Citroën Ami is a supermini produced by the French automaker Citroën from 1961 to 1978. The Ami was for some years the best-selling car model in France.