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.
Similarly, nodes can be removed and new ones added by dragging to/from below the tree.
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
  (CLAUSE
    (CORE
      (PP-PERI
        (CORE_P
          (NUC_P (P 0=Before))
          (NP (OP-DEF 1=the) (CORE_N (NUC_N (N-PROP 2=Revolution))))))
      (NP (PRO 3=they))
      (NUC (AUX-ASP 5=been) (V 7=oppressed))
      (ADVP-PERI (CORE_ADV (NUC_ADV (ADV 6=hideously))))
      (PP (P 8=by) (NP (OP-DEF 9=the) (CORE_N (NUC_N (N 10=capitalists))))))
    (OP-TNS 4=had))
  (CLAUSE
    (, 11=,)
    (CLAUSE
      (CORE (NP (PRO 12=they)) (NUC (AUX-ASP 14=been) (V 15=starved)))
      (OP-TNS 13=had))
    (CLAUSE (CLM 16=and) (CORE (NUC (V 17=flogged)))))
  (CLAUSE
    (, 18=,)
    (CORE
      (CORE (NP (CORE_N (NUC_N (N 19=women)))) (NUC (AUX-ASP 21=been) (V 22=forced)))
      (CORE
        (CLM 23=to)
        (NUC (V 24=work))
        (PP-PERI
          (CORE_P
            (NUC_P (P 25=in))
            (NP (OP-DEF 26=the) (CORE_N (NUC_N (N 27=coal) (N 28=mines))))))))
    (OP-TNS 20=had))
  (SENTENCE-PERI
    (-LRB- 29=#LRB#)
    (CLAUSE
      (CORE
        (NP (CORE_N (NUC_N (N 30=women))))
        (ADVP-PERI (CORE_ADV (NUC_ADV (ADV 31=still))))
        (NUC (V 33=work))
        (PP-PERI
          (CORE_P
            (NUC_P (P 34=in))
            (NP (OP-DEF 35=the) (CORE_N (NUC_N (N 36=coal) (N 37=mines)))))))
      (OP-TNS 32=did)
      (PP-PERI
        (, 38=,)
        (CORE_P
          (NUC_P (P 39=as))
          (NP
            (OP-DEF 40=a)
            (CORE_N
              (NUC_N (N 41=matter))
              (PP (P 42=of) (NP (CORE_N (NUC_N (N 43=fact))))))))))
    (-RRB- 44=#RRB#))
  (, 45=,)
  (CLAUSE
    (CORE
      (NP (CORE_N (NUC_N (N 46=children))))
      (NUC (AUX-ASP 48=been) (V 49=sold))
      (PP
        (CORE_P
          (NUC_P (P 50=into))
          (NP (OP-DEF 51=the) (CORE_N (NUC_N (N 52=factories))))))
      (PP-PERI
        (CORE_P
          (NUC_P (P 53=at))
          (NP
            (OP-DEF 54=the)
            (CORE_N
              (NUC_N (N 55=age))
              (PP (P 56=of) (NP (CORE_N (NUC_N (N 57=six))))))))))
    (OP-TNS 47=had))
  (. 58=.))