A skateboarder at a skate park attempting a rail slide trick.
A person on a skateboard does a trick.
Not all people who skateboard does a trick. Not every skateboarder does the same trick.
exists e1 s1 x1 x2 x3 x4 x5 x6.(a_topic(x1) & at(x1,x2) & Theme(e1,x4) & Actor(e1,x3) & v_attempt(e1) & n_trick(x4) & of(x4,x6) & n_slide(x6) & of(x4,x5) & n_rail(x5) & (x2 = x3) & n_park(x2) & a_skate(s1) & Theme(s1,x2) & n_skateboarder(x1))
exists e1 x1 x2 x3.(Theme(e1,x3) & Actor(e1,x1) & v_do(e1) & n_trick(x3) & on(x1,x2) & n_skateboard(x2) & n_person(x1))