The helmeted boy is doing a stunt on a skateboard.
A skateboarder in protective gear is doing tricks.
A skateboarder is a boy, helmeted means he is in protective gear, and doing a stunt must be doing tricks.
exists e1 s1 x1 x2 x3.(n_boy(x1) & a_helmeted(s1) & Theme(s1,x1) & Theme(e1,x2) & Actor(e1,x1) & v_do(e1) & on(x2,x3) & n_skateboard(x3) & n_stunt(x2))
exists e1 s1 x1 x2 x3.(Theme(e1,x3) & Actor(e1,x1) & v_do(e1) & n_trick(x3) & in(x1,x2) & n_gear(x2) & a_protective(s1) & Theme(s1,x2) & n_skateboarder(x1))