A person standing a rocky ridge.
A person is on natural terrain.
A rocky ridge is a type of natural terrain.
exists e1 s1 x1 x2 x3.(a_topic(x1) & n_ridge(x3) & a_rocky(s1) & Theme(s1,x3) & Time(e1,x3) & Actor(e1,x2) & v_stand(e1) & (x1 = x2) & n_person(x1))
exists p1 x1.(exists s1 x2.(on(x1,x2) & n_terrain(x2) & a_natural(s1) & Theme(s1,x2)) & n_person(x1))