arc(r_0016_0003__must_r_0016_0004__be_r_0016_0005__observed,r_0016_0001__These_r_0016_0002__rules,arg1).

( (IP-MAT (NP-SBJ;{RULES} (D These;{these})
                          (NS rules;{rule}))
          (MD;~cat_Vi must;{must})
          (IP-INF-CAT (BE;~cat_Ve_passive_ be;{be})
                      (IP-PPL-CAT (NP-LGS *)
                                  (VVN;~Tn observed;{observe})))
          (PUNC .))
  (ID 16_a_johnson_letter))