Complex sentence: The Chester Vase is a Group 3 flat horse race in the United Kingdom for three-year-old thoroughbred colts and geldings run over a distance of 1 mile 4 furlongs and 66 yards (2,474 metres) at Chester Racecourse in May.
Split into simpler sentences: The Chester Vase is a Group 3 flat horse race in the United Kingdom for three-year-old thoroughbred colts and geldings. It is run over a distance of 1 mile 4 furlongs and 66 yards (2,474 metres) at Chester Racecourse in May.