A young boy plays on a swing.
A young boy in a hat is swinging.
Not all boys wear a hat while swinging
exists e1 s1 x1 x2.(on(e1,x2) & n_swing(x2) & Actor(e1,x1) & v_play(e1) & n_boy(x1) & a_young(s1) & Theme(s1,x1))
exists e1 s1 x1 x2.(Actor(e1,x1) & v_swing(e1) & in(x1,x2) & n_hat(x2) & n_boy(x1) & a_young(s1) & Theme(s1,x1))