Group of young women and men dressed formally eat their lunches.
They were at a conference.
People can be dressed nice without having been at a conference.
exists e1 e2 s1 s2 x1 x2 x3 x4 x5 x6.(ne_org_group(x1) & Theme(e2,x6) & Actor(e2,x1) & v_eat(e2) & n_lunch(x6) & of(x6,x3) & n_thing(x3) & of(x1,x2) & a_formally(s2) & Manner(e1,s2) & Theme(e1,x5) & v_dress(e1) & (x2 = x5) & n_man(x4) & n_woman(x3) & subset_of(x4,x2) & subset_of(x3,x2) & a_young(s1) & Theme(s1,x2))
exists p1 x1.(n_thing(x1) & exists x2.(at(x1,x2) & n_conference(x2)))