A little boy is playing on a wet stone surface.
a boy is playing leapfrog on wet stone
A boy can be playing something other than leapfrog.
exists e1 s1 s2 x1 x2 x3.(on(e1,x2) & n_surface(x2) & of(x2,x3) & n_stone(x3) & a_wet(s2) & Theme(s2,x2) & Actor(e1,x1) & v_play(e1) & n_boy(x1) & a_little(s1) & Theme(s1,x1))
exists e1 s1 x1 x2 x3.(on(e1,x3) & n_stone(x3) & a_wet(s1) & Theme(s1,x3) & Theme(e1,x2) & Actor(e1,x1) & v_play(e1) & n_leapfrog(x2) & n_boy(x1))