Some people walk past a large billboard.
Some people walk past a high structure that's a water tower.
The structure can not be both a large billboard and a water tower.
exists e1 s1 x1 x2.(past(e1,x2) & n_billboard(x2) & a_large(s1) & Theme(s1,x2) & Actor(e1,x1) & v_walk(e1) & n_people(x1))
exists e1 p1 s1 x1 x2 x3.(past(e1,x2) & exists x4 x5.((x3 = x4) & n_tower(x4) & of(x4,x5) & n_water(x5)) & (x2 = x3) & n_structure(x2) & a_high(s1) & Theme(s1,x2) & Actor(e1,x1) & v_walk(e1) & n_people(x1))