A group of adults and children doing some activity on a sidewalk outside.
People are
People are either doing something, or simply 'are' i.e. existing.
exists e1 x1 x2 x3 x4 x5 x6 x7 x8.(a_topic(x1) & of(x1,x2) & on(e1,x7) & n_outside(x7) & of(x7,x8) & n_sidewalk(x8) & Theme(e1,x6) & Actor(e1,x5) & v_do(e1) & n_activity(x6) & (x2 = x5) & subset_of(x4,x2) & n_child(x4) & subset_of(x3,x2) & n_adult(x3) & n_group(x1))
exists e1 x1.(Actor(e1,x1) & v_be(e1) & n_people(x1))