Teenagers are interacting with elderly people in a common room.
The two groups are talking.
Teenagers and elderly people interacting does not mean they are separated in two groups
exists e1 s1 s2 x1 x2 x3.(in(e1,x3) & n_room(x3) & a_common(s2) & Theme(s2,x3) & with(e1,x2) & n_people(x2) & a_elderly(s1) & Theme(s1,x2) & Actor(e1,x1) & v_interact(e1) & n_teenager(x1))
exists e1 x1.(n_group(x1) & card_eq_2(x1) & Actor(e1,x1) & v_talk(e1))