Three people singing into a microphone.
People are using a microphone.
If they are singing into a microphone, they are using a microphone.
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.(Theme(e1,x2) & Actor(e1,x1) & v_use(e1) & n_microphone(x2) & n_people(x1))