a boy playing with balloons.
A boy is playing with a ball.
a person is either playing with balloons or a ball not both
exists x1 x2 x3.(a_topic(x1) & with(x1,x3) & n_balloon(x3) & n_playing(x1) & of(x1,x2) & n_boy(x2))
exists e1 x1 x2.(with(e1,x2) & n_ball(x2) & Actor(e1,x1) & v_play(e1) & n_boy(x1))