10_a_lob_n01
They might have been arranging a supper party .

%3 0010_0002__might_0010_0003__have_0010_0004__been_0010_0005__arranging might_have_been_arranging 0010_0001__They they 0010_0002__might_0010_0003__have_0010_0004__been_0010_0005__arranging->0010_0001__They [arg0] 0010_0006__a_0010_0007__suppe0010_0008__party a_supper_party 0010_0002__might_0010_0003__have_0010_0004__been_0010_0005__arranging->0010_0006__a_0010_0007__suppe0010_0008__party [arg1]
arc(r_0010_0002__might_r_0010_0003__have_r_0010_0004__been_r_0010_0005__arranging,r_0010_0001__They,arg0).
arc(r_0010_0002__might_r_0010_0003__have_r_0010_0004__been_r_0010_0005__arranging,r_0010_0006__a_r_0010_0007__supper_r_0010_0008__party,arg1).


IP-MAT NP-SBJ PRO They MD;~cat_Vi might IP-INF-CAT HV;~cat_Ve have IP-PPL-CAT BEN;~cat_Vg been IP-PPL-CAT VAG arranging NP-OB1 D a N supper N party PUNC .
( (IP-MAT (NP-SBJ (PRO They;{they}))
          (MD;~cat_Vi might;{may})
          (IP-INF-CAT (HV;~cat_Ve have;{have})
                      (IP-PPL-CAT (BEN;~cat_Vg been;{be})
                                  (IP-PPL-CAT (VAG arranging;{arrange})
                                              (NP-OB1 (D a;{a})
                                                      (N supper;{supper})
                                                      (N party;{party})))))
          (PUNC .))
  (ID 10_a_lob_n01))