A girl is on the ground with a football on her head.
The girl is sitting on the ground.
On the ground does not imply sitting on the ground.
exists p1 x1 x2 x4.(n_head(x4) & of(x4,x2) & n_female(x2) & n_ground(x2) & exists x3.(on(x1,x2) & with(x2,x3) & on(x3,x4) & n_football(x3)) & n_girl(x1))
exists e1 x1 x2.(n_ground(x2) & n_girl(x1) & on(e1,x2) & Actor(e1,x1) & v_sit(e1))