A guy on Rollerblades is grinding on a rail in a skate park.
The guy is doing tricks on his rollerblades.
Grinding on a rail does not imply tricks.
exists e1 x1 x2 x3 x4 x5.(ne_org_rollerblades(x2) & on(e1,x3) & in(x3,x4) & n_park(x4) & of(x4,x5) & n_skate(x5) & n_rail(x3) & Actor(e1,x1) & v_grind(e1) & on(x1,x2) & n_guy(x1))
exists e1 x1 x2 x3.(n_rollerblade(x3) & of(x3,x1) & n_male(x1) & n_guy(x1) & on(e1,x3) & Theme(e1,x2) & Actor(e1,x1) & v_do(e1) & n_trick(x2))