A boy with a ball playing on a playground.
A boy is playing with a basketball.
The ball does not necessarily have to be a basketball
exists x1 x2 x3 x4.(a_topic(x1) & with(x1,x2) & on(x2,x4) & n_playground(x4) & n_playing(x2) & of(x2,x3) & n_ball(x3) & n_boy(x1))
exists e1 x1 x2.(with(e1,x2) & n_basketball(x2) & Actor(e1,x1) & v_play(e1) & n_boy(x1))