A group of people racing horses on a beach.
cars racing on the beach.
Horses can not become cars
exists e1 x1 x2 x3 x4 x5.(a_topic(x1) & of(x1,x2) & Theme(e1,x4) & Actor(e1,x3) & v_race(e1) & on(x4,x5) & n_beach(x5) & n_horse(x4) & (x2 = x3) & n_people(x2) & n_group(x1))
exists e1 x1 x2.(n_beach(x2) & on(e1,x2) & Actor(e1,x1) & v_race(e1) & n_car(x1))