Complex sentence: The Middleton Stakes is a Group 3 flat horse race in the United Kingdom for four-year-old and above thoroughbred fillies and mares run over a distance of 1 mile 2 furlongs and 88 yards (2,092 metres) at York Racecourse in May.
Split into simpler sentences: The Middleton Stakes is a Group 3 flat horse race in the United Kingdom for four-year-old and above thoroughbred fillies and mares. It is run over a distance of 1 mile 2 furlongs and 88 yards (2,092 metres) at York Racecourse in May.