Four people are walking on a sidewalk.
A group is outside.
sidewalks are only built on the outside, A group is another descriptive saying that means more than one person
exists e1 x1 x2.(on(e1,x2) & n_sidewalk(x2) & Actor(e1,x1) & v_walk(e1) & n_people(x1) & card_eq_4(x1))
exists s1 x1.(Theme(s1,x1) & a_outside(s1) & n_group(x1))