Two dogs on the beach fight over a stick.
There two dogs on a beach.
On a beach is a rephrasing of on the beach.
exists x1 x2 x3 x4.(n_fight(x2) & of(x2,x3) & n_beach(x3) & a_topic(x1) & on(x1,x2) & over(x2,x4) & n_stick(x4) & n_dog(x1) & card_eq_2(x1))
(x)