A nude woman submerges herself in a natural pool.
A naked lady goes under water.
Nude is another word for naked, and natural pools are normally filled with water.  Submerges is defined as going under the surface of a liquid.
exists e1 s1 s2 x1 x2.(in(e1,x2) & n_pool(x2) & a_natural(s2) & Theme(s2,x2) & Theme(e1,x2) & Actor(e1,x1) & v_submerge(e1) & n_female(x2) & n_woman(x1) & a_nude(s1) & Theme(s1,x1))
exists e1 s1 x1 x2.(under(e1,x2) & n_water(x2) & Actor(e1,x1) & v_go(e1) & n_lady(x1) & a_naked(s1) & Theme(s1,x1))