A group of musicians playing on stage.
A group of musicians are leaving the auditorium.
The band can't be playing and leaving at the same time.
exists e1 x1 x2 x3 x4.(a_topic(x1) & on(e1,x4) & n_stage(x4) & Actor(e1,x3) & v_play(e1) & (x1 = x3) & of(x1,x2) & n_musician(x2) & n_group(x1))
exists e1 x1 x2 x3.(n_auditorium(x3) & Theme(e1,x3) & Actor(e1,x1) & v_leave(e1) & of(x1,x2) & n_musician(x2) & n_group(x1))