A young person smoking a cigarette.
This is an underage smoker.
A young person is not always an underage person.
exists e1 s1 x1 x2 x3.(a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_smoke(e1) & n_cigarette(x3) & (x1 = x2) & n_person(x1) & a_young(s1) & Theme(s1,x1))
exists p1 x1.(n_thing(x1) & exists x2 x3.((x1 = x2) & n_smoker(x2) & of(x2,x3) & n_underage(x3)))