A group of people in green shirts are walking along a beach.
A group of people in blue shirts are walking along a beach.
green shirts can't be blue shirts
exists e1 s1 x1 x2 x3 x4.(along(e1,x4) & n_beach(x4) & Actor(e1,x1) & v_walk(e1) & of(x1,x2) & in(x2,x3) & n_shirt(x3) & a_green(s1) & Theme(s1,x3) & n_people(x2) & n_group(x1))
exists e1 s1 x1 x2 x3 x4.(along(e1,x4) & n_beach(x4) & Actor(e1,x1) & v_walk(e1) & of(x1,x2) & in(x2,x3) & n_shirt(x3) & a_blue(s1) & Theme(s1,x3) & n_people(x2) & n_group(x1))