There are birds on the boy
The boy is playing with birds
If the birds are on the boy he could be playing with them.
exists p1 x1 x3.(n_boy(x3) & exists x2.((x1 = x2) & on(x2,x3) & n_bird(x2)))
exists e1 x1 x2.(n_boy(x1) & with(e1,x2) & n_bird(x2) & Actor(e1,x1) & v_play(e1))