A dog is digging a hole in the sand.
A dog digs in the sand at a beach.
not every beach has sand.
exists e1 x1 x2 x3.(n_sand(x3) & in(e1,x3) & Theme(e1,x2) & Actor(e1,x1) & v_dig(e1) & n_hole(x2) & n_dog(x1))
exists e1 x1 x2 x3.(n_sand(x2) & at(e1,x3) & n_beach(x3) & in(e1,x2) & Actor(e1,x1) & v_dig(e1) & n_dog(x1))