A little boy stands in the surf.
A boy napping
If the boy stands in the surf, he's obviously not napping.
exists e1 s1 x1 x2.(n_surf(x2) & in(e1,x2) & Actor(e1,x1) & v_stand(e1) & n_boy(x1) & a_little(s1) & Theme(s1,x1))
exists e1 x1 x2.(a_topic(x1) & Actor(e1,x2) & v_nap(e1) & (x1 = x2) & n_boy(x1))