Two houses and fire
Two houses underwater.
Two houses and fire in no way refer to two houses underwater.
exists s1 x1 x2.(n_fire(x2) & n_house(x1) & card_eq_2(x1) & subset_of(x2,s1) & subset_of(x1,s1) & a_topic(s1))
exists x1 x2.(a_topic(x1) & Time(x1,x2) & n_underwater(x2) & n_house(x1) & card_eq_2(x1))