Young people are walking on the street in the evening.
An old couple are playing chess
young people and an old couple are two different groups of people.
exists e1 s1 x1 x2 x3.(n_evening(x3) & n_street(x2) & in(e1,x3) & on(e1,x2) & Actor(e1,x1) & v_walk(e1) & n_people(x1) & a_young(s1) & Theme(s1,x1))
exists e1 s1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_play(e1) & n_chess(x2) & n_couple(x1) & a_old(s1) & Theme(s1,x1))