Baby sitting at a beach.
Only an old man is sitting on the beach.
One can only be a baby or an old man.
exists e1 x1 x2.(ne_nam_baby(x1) & at(e1,x2) & n_beach(x2) & Actor(e1,x1) & v_sit(e1))
exists e1 s1 x1 x2 x3 x5.(n_beach(x5) & n_beach(x3) & all e2 x4.((on(e2,x5) & Actor(e2,x4) & v_sit(e2)) -> (x1 = x4)) & (x1 = x2) & on(e1,x3) & Actor(e1,x2) & v_sit(e1) & n_man(x2) & a_old(s1) & Theme(s1,x2))