Hello! I heard you were an expert on horse racing. What can you tell me about it?
I sure am! Horse racing is an equestrian performance sport, involving 2 or more horses ridden by jockeys and driven over a set distance.
Wow! do you know when it started? Or anything else interesting?
I know that it is an incredibly ancient sport and has remained unchanged since its earliest times. But not sure on when it exactly started
Do you know what any of the popular horse races are? Or popular/famous horses?
Washington Park Race Track was a popular race venue in Chicago from 1884 until 1977.
Huh! what else do you know about horse racing?
There are ancient records that indicate horse racing occurred in Ancient Greece, Babylon, Syria, and Egypt!
I think I've seen pictures of ancient art depicting that. 
You probably have. They even play an important part of myth and legend in stories involving Odin and Hrungnir of Norse myth.