A costume party in full swing.
This is a Halloween party.
Not all costume parties are a Halloween party.
exists s1 s2 x1 x2.(a_topic(x1) & in(x1,x2) & n_swing(x2) & a_full(s2) & Theme(s2,x2) & n_party(x1) & a_costume(s1) & Theme(s1,x1))
exists p1 x1.(n_thing(x1) & exists x2 x3.((x1 = x2) & n_party(x2) & (x2 = x3) & ne_org_halloween(x3)))