Simplify the following text for a Grade 6 native English-speaking person.
Original: Whatever the veracity of such reports , it is extremely rare that a shark will feed on a pilot fish , and smaller pilot fish are frequently observed swimming into sharks ' mouths to clean away fragments of food from between their teeth .
Simplified: Pilot fish follow sharks because other animals which might eat the pilot fish will not come near a shark . In return , sharks do not eat pilot fish because pilot fish eat the parasites which feed off sharks .