lot of pigeons roaming on the street enjoying the sun.
the dogs ate the birds
If there are pigeons around, then they can't have been eaten already, and they certainly wouldn't be enjoying themselves if they were.
exists e1 e2 x1 x2 x3 x4 x5.(n_sun(x5) & n_street(x4) & a_topic(x1) & of(x1,x2) & for(e1,e2) & Theme(e2,x5) & Actor(e2,x3) & v_enjoy(e2) & on(e1,x4) & Actor(e1,x3) & v_roam(e1) & (x2 = x3) & n_pigeon(x2) & n_lot(x1))
exists e1 x1 x2.(n_bird(x2) & n_dog(x1) & Theme(e1,x2) & Actor(e1,x1) & v_eat(e1))