A man standing by a yellow sign.
A man stands by the red sign.
The sign can't be all yellow and all red at the same time.
exists s1 x1 x2 x3.(a_topic(x1) & by(x1,x3) & n_sign(x3) & a_yellow(s1) & Theme(s1,x3) & n_standing(x1) & of(x1,x2) & n_man(x2))
exists e1 s1 x1 x2.(n_sign(x2) & a_red(s1) & Theme(s1,x2) & by(e1,x2) & Actor(e1,x1) & v_stand(e1) & n_man(x1))