A woman whose head is not visible walks in front of a bus with an advertisement on its side.
The advertisement has a similar looking woman on it.
If the head of the woman walking isn't visible than  you can't know if she is similar looking to the ad on the side of the bus.
exists e1 x1 x2 x3 x4 x5 x6.(in(e1,x3) & of(x3,x4) & with(x4,x5) & on(x5,x6) & n_side(x6) & of(x6,x1) & n_thing(x1) & n_advertisement(x5) & n_bus(x4) & n_front(x3) & Actor(e1,x1) & v_walk(e1) & -exists s1.(Theme(s1,x2) & a_visible(s1)) & n_head(x2) & of(x2,x1) & n_woman(x1))
exists e2 e1 s1 x1 x2.(n_thing(x1) & n_advertisement(x1) & Theme(e2,x2) & Actor(e2,x1) & v_have(e2) & on(x2,x1) & n_woman(x2) & Actor(e1,x2) & v_look(e1) & a_similar(s1) & Theme(s1,x2))