The rider skates down the stair rails.
The rider climbs up a mountain.
The rider who skates cannot also simultaneously be the rider who climbs
exists e1 s1 x1 x2 x3.(n_rail(x2) & of(x2,x3) & n_stair(x3) & n_rider(x1) & a_down(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_skate(e1))
exists e1 s1 x1 x2.(n_rider(x1) & a_up(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_climb(e1) & n_mountain(x2))