Two people walking outside a castle.
Two people are sight seeing.
Two people walking outside doesn't mean sight seeing.
exists e1 x1 x2 x3.(a_topic(x1) & outside(e1,x3) & n_castle(x3) & Actor(e1,x2) & v_walk(e1) & (x1 = x2) & n_people(x1) & card_eq_2(x1))
exists e1 x1 x2 x3.(Time(e1,x3) & n_sight(x3) & Theme(e1,x2) & Actor(e1,x1) & v_see(e1) & n_thing(x2) & n_people(x1) & card_eq_2(x1))