An all male four piece band plays on stage.
An all boy four piece band plays on stage.
Not every male is a boy.
exists e1 x1 x2 x3 x4.(Time(e1,x4) & n_band(x4) & on(e1,x3) & n_stage(x3) & Actor(e1,x1) & v_play(e1) & n_piece(x1) & card_eq_4(x1) & of(x1,x2) & n_male(x2))
exists e1 x1 x2 x3 x4.(Time(e1,x4) & n_band(x4) & on(e1,x3) & n_stage(x3) & Actor(e1,x1) & v_play(e1) & n_piece(x1) & card_eq_4(x1) & of(x1,x2) & n_boy(x2))