A child on a red slide.
A child is playing on a swingset.
Children often play on structures other than on a swingset.
exists s1 x1 x2.(a_topic(x1) & on(x1,x2) & n_slide(x2) & a_red(s1) & Theme(s1,x2) & n_child(x1))
exists e1 x1 x2.(on(e1,x2) & n_swingset(x2) & Actor(e1,x1) & v_play(e1) & n_child(x1))