Two dogs chasing a ball.
The dogs are chasing a stick.
If dogs are chasing a ball hey are not chasing a stick.
exists e1 x1 x2 x3.(a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_chase(e1) & n_ball(x3) & (x1 = x2) & n_dog(x1) & card_eq_2(x1))
exists e1 x1 x2.(n_dog(x1) & Theme(e1,x2) & Actor(e1,x1) & v_chase(e1) & n_stick(x2))