Two rock and roll performers on stage playing their guitars performing in front of a crowd .
It is certain that a band is playing a slow ballad to a swarm of adoring fans .
It is probably not the case that a band is playing a slow ballad to a swarm of adoring fans .
It is certain that a band is playing a slow ballad to a swarm of adoring fans .
A band is playing a slow ballad to a swarm of adoring fans .