a boy smiles underwater.
A boy is relaxing on the beach.
You cannot be on a beach and underwater simultaneously.
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_smile(e1) & n_underwater(x2) & n_boy(x1))
exists e1 x1 x2.(n_beach(x2) & on(e1,x2) & Actor(e1,x1) & v_relax(e1) & n_boy(x1))