Two officers sit on horses in a urban setting.
two men sit atop horses
This allows us to infer that the officers are riding atop the horses, rather than the horses are laying down and the officers are sitting on their sides.
exists e1 s1 x1 x2 x3.(in(e1,x3) & n_setting(x3) & a_urban(s1) & Theme(s1,x3) & on(e1,x2) & n_horse(x2) & Actor(e1,x1) & v_sit(e1) & n_officer(x1) & card_eq_2(x1))
exists e1 x1 x2.(r_atop(e1) & Time(e1,x2) & n_horse(x2) & Actor(e1,x1) & v_sit(e1) & n_man(x1) & card_eq_2(x1))