A man in a red sleeveless shirt rides a horse.
The man is on a trail.
Rides a horse does not necessarily mean on a trail.
exists e1 s1 s2 x1 x2 x3.(Theme(e1,x3) & Actor(e1,x1) & v_ride(e1) & n_horse(x3) & in(x1,x2) & n_shirt(x2) & a_sleeveless(s2) & Theme(s2,x2) & a_red(s1) & Theme(s1,x2) & n_man(x1))
exists p1 x1.(n_man(x1) & exists x2.(on(x1,x2) & n_trail(x2)))