Complex sentence: The Sydney Autumn Racing Carnival featuring the richest 2 year old horse race in the world the Golden Slipper, is run in April every year, and the Medibank International tennis tournament is held in January prior to the Australian Open.
Split into simpler sentences: The Sydney Autumn Racing Carnival features the richest two year old horse race in the world, the Golden Slipper Stakes, which is run in April every year. The Medibank International tennis tournament is held in January prior to the Australian Open.