Simplify the following text for a Grade 7 native English-speaking person.
Original: Super Bowl XXXIV featured the National Football Conference ( NFC ) champion St. Louis Rams and the American Football Conference ( AFC ) champion Tennessee Titans in an American football game to decide the National Football League ( NFL ) champion for the 1999 regular season .
Simplified: Super Bowl XXXIV ( or Super Bowl 34 ) was a Super Bowl game between the St. Louis Rams and the Tennessee Titans in the National Football League ( NFL ) champion for the 1999 regular season .