A group of people walking on the side of a railroad track.
The people are all friends.
Groups of people are not always friends.
exists e1 x1 x2 x3 x4 x5 x6.(n_side(x4) & a_topic(x1) & of(x1,x2) & on(e1,x4) & of(x4,x5) & n_track(x5) & of(x5,x6) & n_railroad(x6) & Actor(e1,x3) & v_walk(e1) & (x2 = x3) & n_people(x2) & n_group(x1))
exists p1 x1.(n_people(x1) & all x2.(n_friend(x2) -> (x1 = x2)))