Children are pulling on a rope.
they are playing tug o war
Children pulling on a rope are not necessarily playing tug o war.
exists e1 x1 x2.(on(e1,x2) & n_rope(x2) & Actor(e1,x1) & v_pull(e1) & n_child(x1))
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_play(e1) & n_war(x2) & of(x2,x3) & n_o(x3) & of(x2,x1) & n_tug(x1) & n_thing(x1))