A girl plays on a red toy.
The girls red toy is a firetruck.
The toy could be many things besides a firetruck.
exists e1 s1 x1 x2.(on(e1,x2) & n_toy(x2) & a_red(s1) & Theme(s1,x2) & Actor(e1,x1) & v_play(e1) & n_girl(x1))
exists p1 s1 x1 x2.(n_toy(x1) & a_red(s1) & Theme(s1,x1) & of(x1,x2) & n_girl(x2) & exists x3.((x1 = x3) & n_firetruck(x3)))