A man painting over graffiti.
A man is cleaning up the graffiti on a wall.
Not all graffiti is on a wall.
exists x1 x2 x3.(a_topic(x1) & over(x1,x3) & n_graffitus(x3) & n_painting(x1) & of(x1,x2) & n_man(x2))
exists e1 s1 x1 x2 x3.(n_graffitus(x2) & on(e1,x3) & n_wall(x3) & a_up(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_clean(e1) & n_man(x1))