a snowboarder jumps on the snow.
The man is sitting in some snow.
The man would not be sitting while he jumps.
exists e1 x1 x2.(n_snow(x2) & on(e1,x2) & Actor(e1,x1) & v_jump(e1) & n_snowboarder(x1))
exists e1 x1 x2.(n_man(x1) & in(e1,x2) & n_snow(x2) & Actor(e1,x1) & v_sit(e1))