Three people singing into a microphone.
Four people are dancing to the music.
The should be either three or four individuals.  They cannot be both singing and dancing.
exists e1 x1 x2 x3.(a_topic(x1) & into(e1,x3) & n_microphone(x3) & Actor(e1,x2) & v_sing(e1) & (x1 = x2) & n_people(x1) & card_eq_3(x1))
exists e1 x1 x2.(n_music(x2) & to(e1,x2) & Actor(e1,x1) & v_dance(e1) & n_people(x1) & card_eq_4(x1))