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
    (CLM 0=But)
    (CORE
      (NP (PRO-DEM 1=there))
      (NUC (V 3=been))
      (NP
        (OP-DEF 4=a)
        (CORE_N
          (NUC_N (N 5=moment))
          (PP
            (P 19=of)
            (NP
              (CORE_N
                (AP-PERI (CORE_A (NUC_A (A 20=luminous))))
                (NUC_N (N 21=certainty))))))
        (SENTENCE-PERI
          (, 22=,)
          (CLAUSE
            (CLAUSE
              (PrCS (ADVP-REL (ADV-REL 23=when)))
              (CORE
                (NP
                  (OP-DEF 24=each)
                  (CORE_N
                    (AP-PERI (CORE_A (NUC_A (A 25=new))))
                    (NUC_N (N 26=suggestion))
                    (PP
                      (P 27=of)
                      (NP (CORE_N (NUC_N (N-PROP 28=O'Brien))) (POS 29='s)))))
                (NUC (V 31=filled) (PRT 32=up))
                (NP
                  (OP-DEF 33=a)
                  (CORE_N
                    (NUC_N (N 34=patch))
                    (PP (P 35=of) (NP (CORE_N (NUC_N (N 36=emptiness))))))))
              (OP-TNS 30=had))
            (CLAUSE
              (CLM 37=and)
              (CORE
                (NUC
                  (NUC (V 38=become))
                  (NUC
                    (NP
                      (CORE_N
                        (NUC_N
                          (AP-PERI (CORE_A (NUC_A (A 39=absolute))))
                          (N 40=truth))))))))
            (, 41=,)))
        (SENTENCE-PERI
          (CLM 42=and)
          (CLAUSE
            (PrCS (ADVP-REL (ADV-REL 43=when)))
            (CORE
              (QP (CORE_Q (NUC_Q (QNT 44=two))))
              (QP (CLM 45=and) (CORE_Q (NUC_Q (QNT 46=two))))
              (OP-MOD 47=could)
              (NUC (AUX-ASP 49=been) (QP (CORE_Q (NUC_Q (QNT 50=three)))))
              (ADVP-PERI
                (CORE_ADV
                  (NUC_ADV (ADV 51=as) (ADV 52=easily))
                  (PP (P 53=as) (NP (CORE_N (NUC_Q (QNT 54=five)))))))
              (, 55=,))
            (OP-TNS 48=have)
            (CLAUSE-PERI
              (CLM 56=if)
              (CORE
                (NP (PRO-DEM 57=that))
                (NUC
                  (AUX-TNS 58=were)
                  (CLAUSE
                    (PrCS (NP-WH (PRO-WH 59=what)))
                    (CORE (NUC (AUX-TNS 60=was) (V 61=needed)))))))))))
    (OP-TNS 2=had))
  (SENTENCE-PERI
    (. 6=-)
    (CLAUSE
      (CORE
        (NP (PRO 7=he))
        (OP-NEG 9=not)
        (NUC (V 10=know))
        (QP (CORE_Q (ADVP-WH (ADV-WH 11=how)) (NUC_Q (QNT 12=long)))))
      (OP-TNS 8=did))
    (PoDP
      (NP
        (CORE_N (, 13=,) (QP (CORE_Q (NUC_Q (QNT 14=thirty)))) (NUC_N (N 15=seconds)))
        (ADVP-PERI (, 16=,) (CORE_ADV (NUC_ADV (ADV 17=perhaps))))))
    (. 18=-))
  (. 62=.))