A band is playing on the sidewalk while people watch.
The band's audience sings to the music played.
Not every band's audience sings while watching them.
exists e1 p1 x1 x2.(n_sidewalk(x2) & exists e2 x3.(Actor(e2,x3) & v_watch(e2) & n_people(x3)) & while(e1,p1) & on(e1,x2) & Actor(e1,x1) & v_play(e1) & n_band(x1))
exists e1 x1 x2 x3 x4.(n_music(x4) & n_sing(x2) & of(x2,x3) & n_audience(x3) & of(x2,x1) & n_band(x1) & Actor(e1,x2) & v_play(e1) & to(x2,x4))