RRGparbank

To change a label, click on a node to select a different label from a list. The syntactic category and the function tag (before and after the dash "-") must be selected separately by clicking on the corresponding part of the label.
To add a function tag to a node that does not have one yet, drag it from the list of function tags onto the node.
Re-attach a node by dragging and dropping it on a new parent. This can be used to created discontinuous constituents.
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Finally, the bracketing can be edited manually in the text box below the tree; press "validate" to update the tree. Whitespace is ignored. Each token must have a dedicated POS tag.

				[...wait for it...]

(SENTENCE
  (PrDP
    (PP (CORE_P (NUC_P (P 0=In)) (NP (CORE_N (NUC_N (N 1=addition))))))
    (, 2=,))
  (CLAUSE
    (CLAUSE
      (CORE
        (NP (OP-DEF 3=any) (CORE_N (NUC_N (N 4=word))))
        (OP-MOD 18=could)
        (NUC (AUX 19=be) (V 20=negatived))
        (PP
          (CORE_P
            (NUC_P (P 21=by))
            (CORE
              (NUC (V 22=adding))
              (NP
                (OP-DEF 23=the)
                (CORE_N
                  (NUC_N (N 24=affix))
                  (NP (CORE_N (NUC_N (N 25=un) (. 26=-)))))))))))
    (CLAUSE
      (CLM 27=or)
      (CORE
        (OP-MOD 28=could)
        (NUC (AUX 29=be) (V 30=strengthened))
        (PP
          (CORE_P
            (NUC_P (P 31=by))
            (NP
              (OP-DEF 32=the)
              (CORE_N
                (NUC_N (N 33=affix))
                (NP
                  (NP (CORE_N (NUC_N (N 34=plus) (. 35=-))))
                  (NP
                    (, 36=,)
                    (CLM 37=or)
                    (PP-PERI
                      (, 38=,)
                      (CORE_P
                        (NUC_P (P 39=for))
                        (NP
                          (CORE_N
                            (AP-PERI
                              (CORE_A
                                (NUC_A
                                  (ADVP-PERI
                                    (CORE_ADV (NUC_ADV (ADV 40=still))))
                                  (A 41=greater))))
                            (NUC_N (N 42=emphasis)))))
                      (, 43=,))
                    (CORE_N (NUC_N (N 44=doubleplus) (. 45=-))))))))))))
  (CLAUSE-PERI
    (. 5=-)
    (CORE
      (NP (PRO-DEM 6=this))
      (ADVP-PERI (CORE_ADV (NUC_ADV (ADV 7=again))))
      (NUC (V 8=applied))
      (PP-PERI (CORE_P (NUC_P (P 9=in)) (NP (CORE_N (NUC_N (N 10=principle))))))
      (PP
        (P 11=to)
        (NP
          (OP-DEF 12=every)
          (CORE_N
            (NUC_N (N 13=word))
            (PP-PERI
              (CORE_P
                (NUC_P (P 14=in))
                (NP (OP-DEF 15=the) (CORE_N (NUC_N (N 16=language))))))))))
    (. 17=-))
  (. 46=.))