Two teenagers interacting with the elder population.
Some kids and old people.
Two teenagers are some kids.  Old people are a part of an elder population.
exists e1 x1 x2 x3 x4.(n_population(x3) & of(x3,x4) & n_elder(x4) & a_topic(x1) & with(e1,x3) & Actor(e1,x2) & v_interact(e1) & (x1 = x2) & n_teenager(x1) & card_eq_2(x1))
exists s1 s2 x1 x2.(a_topic(s1) & n_people(x2) & a_old(s2) & Theme(s2,x2) & n_kid(x1) & subset_of(x2,s1) & subset_of(x1,s1))