A guitar band is playing on stage.
A band is playing a song for an audience.
Just because a band is playing a song doesn't mean it's for an audience.
exists e1 x1 x2 x3.(on(e1,x3) & n_stage(x3) & Actor(e1,x1) & v_play(e1) & n_band(x1) & of(x1,x2) & n_guitar(x2))
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_play(e1) & for(x2,x3) & n_audience(x3) & n_song(x2) & n_band(x1))