a snowboarder jumps on the snow.
A man is snowboarding on the snow.
A snowboarder does not have to be a man.
exists e1 x1 x2.(n_snow(x2) & on(e1,x2) & Actor(e1,x1) & v_jump(e1) & n_snowboarder(x1))
exists e1 x1 x2.(n_snow(x2) & on(e1,x2) & Actor(e1,x1) & v_snowboard(e1) & n_man(x1))