Guy walking down the street in a dirty city.
A man is walking on a dirty sidewalk.
Not all dirty sidewalks are in dirty cities.
exists e1 s1 x1 x2 x3.(n_street(x2) & ne_nam_guy(x1) & in(e1,x3) & n_city(x3) & a_dirty(s1) & Theme(s1,x3) & down(e1,x2) & Actor(e1,x1) & v_walk(e1))
exists e1 x1 x2 x3.(on(e1,x2) & n_sidewalk(x2) & of(x2,x3) & n_dirty(x3) & Actor(e1,x1) & v_walk(e1) & n_man(x1))