Complex sentence: Runners form teams that race against each other in 9 major divisions.Register is usually in October of each year and the race field has been known to fill up in as little as 5 minutes on registration day.
Split into simpler sentences: Runners form teams that race against each other in 9 major divisions. Registration is usually in October of each year and the race field has been known to fill up in as little as 5 minutes on registration day.