A black-haired swimmer in a pool.
A swimmer in a pool prepares for a race.
Just because a swimmer is in the pool it does not mean they prepares for a race.
exists s1 x1 x2.(a_topic(x1) & in(x1,x2) & n_pool(x2) & n_swimmer(x1) & a_black-haired(s1) & Theme(s1,x1))
exists e1 x1 x2 x3.(for(e1,x3) & n_race(x3) & Actor(e1,x1) & v_prepare(e1) & in(x1,x2) & n_pool(x2) & n_swimmer(x1))