a boy smiles underwater.
The boy is in the ocean.
Underwater does not necessarily imply the ocean.
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_smile(e1) & n_underwater(x2) & n_boy(x1))
exists p1 x1 x2.(n_ocean(x2) & n_boy(x1) & in(x1,x2))