A crowd is watching a rock band perform on stage.
A rock band is perfoming in front of a crowd.
if a rock band perform then they are performing
exists e1 e2 x1 x2 x3 x4 x5.(on(e2,x5) & n_stage(x5) & Actor(e2,x1) & v_perform(e2) & Theme(e1,x3) & Actor(e1,x2) & v_watch(e1) & n_band(x3) & of(x3,x4) & n_rock(x4) & (x1 = x2) & n_crowd(x1))
exists e1 x1 x2 x3 x4.(in(e1,x3) & of(x3,x4) & n_crowd(x4) & n_front(x3) & Actor(e1,x1) & v_perfome(e1) & n_band(x1) & of(x1,x2) & n_rock(x2))