A man does a jumping trick on a skateboard.
Man is skateboarding.
To do tricks on a skateboard is skateboarding.
exists e1 e2 x1 x2 x3.(Theme(e2,x2) & Actor(e2,x1) & v_do(e2) & on(x2,x3) & n_skateboard(x3) & n_trick(x2) & Actor(e1,x2) & v_jump(e1) & n_man(x1))
exists e1 x1.(Actor(e1,x1) & v_skateboard(e1) & n_man(x1))