The two men are riding horses to chase a white horse.
Two horses are following after another horse.
One could infer that two men are riding the two horses.
exists e1 p1 x1 x2.(n_man(x1) & card_eq_2(x1) & Topic(e1,p1) & exists e2 s1 x3.(Theme(e2,x3) & Actor(e2,x1) & v_chase(e2) & n_horse(x3) & a_white(s1) & Theme(s1,x3)) & Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & n_horse(x2))
exists e1 x1 x2.(after(e1,x2) & n_horse(x2) & -(x2 = x1) & n_horse(x1) & n_horse(x1) & Actor(e1,x1) & v_follow(e1) & card_eq_2(x1))