Complex sentence: Sinead Diver (born 17 February 1977) is an Australian long-distance runner who competed in the marathon event at the 2015 World Championships in Athletics in Beijing, China.
Split into simpler sentences: Sinead Diver (born 17 February 1977) is an Australian long-distance runner. She competed in the marathon event at the 2015 World Championships in Athletics in Beijing, China.