Two people play water volleyball in a pool.
They are playing in a pool.
play water volleyball is the same as  playing
exists e1 x1 x2 x3 x4.(in(e1,x4) & n_pool(x4) & Theme(e1,x2) & Actor(e1,x1) & v_play(e1) & n_volleyball(x2) & of(x2,x3) & n_water(x3) & n_people(x1) & card_eq_2(x1))
exists e1 x1.(in(e1,x1) & n_pool(x1) & Actor(e1,x1) & v_play(e1) & n_thing(x1))