Two dogs run side-by-side on the grass.
The two dogs are brother and sister.
Just because two dogs run side-by-side on the grass does not mean that they are brother and sister.
exists e1 s1 x1 x2.(n_grass(x2) & on(e1,x2) & a_side-by-side(s1) & Manner(e1,s1) & Actor(e1,x1) & v_run(e1) & n_dog(x1) & card_eq_2(x1))
exists p1 x1.(n_dog(x1) & card_eq_2(x1) & exists x2 x3 x4.((x1 = x2) & subset_of(x4,x2) & n_sister(x4) & subset_of(x3,x2) & n_brother(x3)))