A young girl is riding a white horse.
The horse is white
young girl is riding a white horse shows that  horse is white
exists e1 s1 s2 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & n_horse(x2) & a_white(s2) & Theme(s2,x2) & n_girl(x1) & a_young(s1) & Theme(s1,x1))
exists s1 x1.(n_horse(x1) & Theme(s1,x1) & a_white(s1))