Example usage for edu.stanford.nlp.trees Tree parent

List of usage examples for edu.stanford.nlp.trees Tree parent

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Introduction

In this page you can find the example usage for edu.stanford.nlp.trees Tree parent.

Prototype

public Tree parent(Tree root)

Source Link

Document

Return the parent of the tree node.

Usage

From source file:edu.cmu.ark.nlp.sent.SentenceSimplifier.java

License:Open Source License

/**
 * e.g., John and James like Susan.  ->  John likes Susan.
 * // w ww .  j  a  v a2  s. co m
 */
private void extractConjoinedNPs(Collection<Question> extracted, Question input) {
    String tregexOpStr;
    TregexPattern matchPattern;
    Tree conjoinedNode;
    Tree parent;

    TregexMatcher matcher;
    Question newQuestion;

    //only extract conjoined NPs that are arguments or adjuncts of the main verb
    // in the tree, this means the closest S will be the one under the root
    tregexOpStr = "NP=parent < (CONJP|CC !< or|nor [ "
            + " $+ /^(N.*|PRP|SBAR)$/=child $-- /^(N.*|PRP|SBAR)$/ | " //there must be a noun on each side of the conjunction
            + " $-- /^(N.*|PRP|SBAR)$/=child $+ /^(N.*|PRP|SBAR)$/ ] ) " //this avoids extracting from flat NPs such as "the smaller and darker form"
            + " !>> (/.*/ $ (CC|CONJP !< or|nor)) " //this cannot be nested within a larger conjunction or followed by a conjunction (we recur later to catch this) 
            + " !$ (CC|CONJP !< or|nor)" + " !.. (CC|CONJP !< or|nor > NP|PP|S|SBAR|VP) !>> SBAR ";
    //+ " >> (ROOT !< (S <+(VP) (/^VB.*$/ < are|were|be|seem|appear))) " ; //don't break plural predicate nominatives (e.g., "John and Mary are two of my best friends.")
    matchPattern = TregexPatternFactory.getPattern(tregexOpStr);
    matcher = matchPattern.matcher(input.getIntermediateTree());
    List<Integer> nodeIndexes = new ArrayList<Integer>();
    List<Integer> parentIDs = new ArrayList<Integer>();

    while (matcher.find()) {
        //store the parents' IDs (in the tree)
        parent = matcher.getNode("parent");
        parentIDs.add(parent.nodeNumber(input.getIntermediateTree()));

        conjoinedNode = matcher.getNode("child");
        //store the conjoined nodes' index into their parent's list of children
        int idx = parent.objectIndexOf(conjoinedNode);
        if (!nodeIndexes.contains(idx))
            nodeIndexes.add(idx);
    }

    //for each of the conjoined children,
    //create a new tree by removing all the nodes they are conjoined with
    Collections.sort(nodeIndexes);//sort, just to keep them in the original order
    for (int i = 0; i < nodeIndexes.size(); i++) {
        newQuestion = input.deeperCopy();

        Tree t = newQuestion.getIntermediateTree();
        parent = t.getNodeNumber(parentIDs.get(i));
        Tree gparent = parent.parent(t);
        conjoinedNode = parent.getChild(nodeIndexes.get(i));
        String siblingLabel;

        //Remove all the nodes that are conjoined
        //with the selected noun (or are conjunctions, commas).
        //These can have labels NP, NN, ..., PRP for pronouns, CC, "," for commas, ":" for semi-colons
        for (int j = 0; j < parent.numChildren(); j++) {
            if (parent.getChild(j) == conjoinedNode)
                continue;
            siblingLabel = parent.getChild(j).label().toString();
            if (siblingLabel.matches("^[NCP,:S].*")) {
                parent.removeChild(j);
                j--;
            }
        }

        //if there is an trivial unary "NP -> NP",
        //remove the parent and put the child in its place
        if (parent.numChildren() == 1 && parent.getChild(0).label().equals("NP")) {
            int tmpIndex = gparent.objectIndexOf(parent);
            gparent.removeChild(tmpIndex);
            gparent.addChild(tmpIndex, parent.getChild(0));
        }

        correctTense(conjoinedNode, gparent);
        addQuotationMarksIfNeeded(newQuestion.getIntermediateTree());

        //if(GlobalProperties.getDebug()) System.err.println("extractConjoinedNPs: "+newQuestion.getIntermediateTree().toString());
        if (this.getComputeFeatures)
            newQuestion.setFeatureValue("extractedFromConjoinedPhrases", 1.0); //old feature name
        if (this.getComputeFeatures)
            newQuestion.setFeatureValue("extractedFromConjoinedNPs", 1.0);
        extracted.add(newQuestion);
    }
}

From source file:edu.cmu.ark.nlp.sent.SentenceSimplifier.java

License:Open Source License

/**
 * e.g., John and Mary like Bill.  -> John LIKES Bill.  Mary LIKES Bill.
 * John and I like Bill -> John LIKES Bill.  I LIKE Bill.
 * John and I are old. -> I IS old. John IS old.
 *///from   www . ja v  a 2s. c  om
private void correctTense(Tree subject, Tree clause) {
    int tmpIndex;
    //correct verb tense when modifying subjects
    for (Tree uncle : clause.getChildrenAsList()) {
        String newVerbPOS = null;
        Tree verbPreterminal = null;
        boolean needToModifyVerb = false;
        //if the node is a subject (i.e., its uncle is a VP), then check
        //to see if its tense needs to be changed
        String headPOS = subject.headPreTerminal(this.hf).label().toString();
        if (uncle.label().toString().equals("VP") && !headPOS.endsWith("S")) {
            verbPreterminal = uncle.headPreTerminal(this.hf);
            //original main verb was plural but the conjoined subject word is singular
            //e.g., John (and Mary) like Bill.  -> John like Bill.
            if ((verbPreterminal.label().toString().equals("VB")
                    || verbPreterminal.label().toString().equals("VBP"))) { //the parser confuses VBP with VB
                if (subject.yield().toString().equals("I") || subject.yield().toString().equals("you")) {
                    newVerbPOS = "VBP";
                } else {
                    newVerbPOS = "VBZ";
                }
                needToModifyVerb = true;
            } else if (verbPreterminal.label().toString().equals("VBD")) {
                newVerbPOS = "VBD";
                needToModifyVerb = true;
            }
        }
        //if needed, change the tense of the verb
        if (needToModifyVerb) {
            String verbLemma = QuestionUtil.getLemma(verbPreterminal.getChild(0).label().toString(),
                    verbPreterminal.label().toString());
            String newVerb;
            //special cases
            if (verbLemma.equals("be") && newVerbPOS.equals("VBD")) {
                if (subject.label().toString().endsWith("S"))
                    newVerb = "were";
                else
                    newVerb = "was";
            } else if (verbLemma.equals("be") && subject.yield().toString().equals("I")
                    && newVerbPOS.equals("VBP")) {
                newVerb = "am";
            } else { //default
                newVerb = this.conjugator.getSurfaceForm(verbLemma, newVerbPOS);
            }
            tmpIndex = verbPreterminal.parent(uncle).objectIndexOf(verbPreterminal);
            Tree verbParent = verbPreterminal.parent(uncle);
            verbParent.removeChild(tmpIndex);
            verbParent.addChild(tmpIndex,
                    QuestionUtil.readTreeFromString("(" + newVerbPOS + " " + newVerb + ")"));
        }
    }
}

From source file:edu.cmu.ark.nlp.sent.SentenceSimplifier.java

License:Open Source License

private void removeConjoinedSiblingsHelper(Tree copy, int childindex) {
    //if(GlobalProperties.getDebug()) System.err.println("removeConjoinedSiblingsHelper: "+copy.toString());
    Tree child = copy.getNodeNumber(childindex);
    Tree parent = child.parent(copy);
    Tree gparent = parent.parent(copy);/*from   ww w  .  jav a  2 s. c  o  m*/

    int parentIdx = gparent.objectIndexOf(parent);

    //By an annoying PTB convention, some verb phrase conjunctions 
    //can conjoin two verb preterminals under a VP,
    //rather than only allowing VP nodes to be conjoined.
    //e.g., John walked and played.
    //So, we add an extra VP node in between if necessary
    if (child.label().toString().startsWith("VB")) {
        gparent.removeChild(parentIdx);
        Tree newTree = factory.newTreeNode("VP", new ArrayList<Tree>());
        newTree.addChild(child);
        gparent.addChild(parentIdx, newTree);
    } else {
        gparent.setChild(parentIdx, child);
    }
}

From source file:edu.cmu.ark.Question.java

License:Open Source License

public List<Tree> findLogicalWordsAboveIntermediateTree() {
    List<Tree> res = new ArrayList<Tree>();

    Tree pred = intermediateTree.getChild(0).headPreTerminal(AnalysisUtilities.getInstance().getHeadFinder());
    String lemma = AnalysisUtilities.getInstance().getLemma(pred.yield().toString(), pred.label().toString());

    String tregexOpStr;//from  w  w w  .  j a v a  2s.c om
    TregexPattern matchPattern;
    TregexMatcher matcher;

    Tree sourcePred = null;
    for (Tree leaf : sourceTree.getLeaves()) {
        Tree tmp = leaf.parent(sourceTree);
        String sourceLemma = AnalysisUtilities.getInstance().getLemma(leaf.label().toString(),
                tmp.label().toString());
        if (sourceLemma.equals(lemma)) {
            sourcePred = tmp;
            break;
        }
    }

    tregexOpStr = "RB|VB|VBD|VBP|VBZ|IN|MD|WRB|WDT|CC=command";
    matchPattern = TregexPatternFactory.getPattern(tregexOpStr);
    matcher = matchPattern.matcher(sourceTree);

    Tree command;
    while (matcher.find() && sourcePred != null) {
        command = matcher.getNode("command");
        if (AnalysisUtilities.cCommands(sourceTree, command, sourcePred)
                && command.parent(sourceTree) != sourcePred.parent(sourceTree)) {
            res.add(command);
        }
    }

    return res;
}

From source file:edu.cmu.ark.SentenceSimplifier.java

License:Open Source License

/**
 * e.g., John and James like Susan.  ->  John likes Susan.
 * //from   w  w  w . ja v  a2  s  .  c  o  m
 */
private void extractConjoinedNPs(Collection<Question> extracted, Question input) {
    String tregexOpStr;
    TregexPattern matchPattern;
    Tree conjoinedNode;
    Tree parent;

    TregexMatcher matcher;
    Question newQuestion;

    //only extract conjoined NPs that are arguments or adjuncts of the main verb
    // in the tree, this means the closest S will be the one under the root
    tregexOpStr = "NP=parent < (CONJP|CC !< or|nor [ "
            + " $+ /^(N.*|PRP|SBAR)$/=child $-- /^(N.*|PRP|SBAR)$/ | " //there must be a noun on each side of the conjunction
            + " $-- /^(N.*|PRP|SBAR)$/=child $+ /^(N.*|PRP|SBAR)$/ ] ) " //this avoids extracting from flat NPs such as "the smaller and darker form"
            + " !>> (/.*/ $ (CC|CONJP !< or|nor)) " //this cannot be nested within a larger conjunction or followed by a conjunction (we recur later to catch this) 
            + " !$ (CC|CONJP !< or|nor)" + " !.. (CC|CONJP !< or|nor > NP|PP|S|SBAR|VP) !>> SBAR ";
    //+ " >> (ROOT !< (S <+(VP) (/^VB.*$/ < are|were|be|seem|appear))) " ; //don't break plural predicate nominatives (e.g., "John and Mary are two of my best friends.")
    matchPattern = TregexPatternFactory.getPattern(tregexOpStr);
    matcher = matchPattern.matcher(input.getIntermediateTree());
    List<Integer> nodeIndexes = new ArrayList<Integer>();
    List<Integer> parentIDs = new ArrayList<Integer>();

    while (matcher.find()) {
        //store the parents' IDs (in the tree)
        parent = matcher.getNode("parent");
        parentIDs.add(parent.nodeNumber(input.getIntermediateTree()));

        conjoinedNode = matcher.getNode("child");
        //store the conjoined nodes' index into their parent's list of children
        int idx = parent.indexOf(conjoinedNode);
        if (!nodeIndexes.contains(idx))
            nodeIndexes.add(idx);
    }

    //for each of the conjoined children,
    //create a new tree by removing all the nodes they are conjoined with
    Collections.sort(nodeIndexes);//sort, just to keep them in the original order
    for (int i = 0; i < nodeIndexes.size(); i++) {
        newQuestion = input.deeperCopy();

        Tree t = newQuestion.getIntermediateTree();
        parent = t.getNodeNumber(parentIDs.get(i));
        Tree gparent = parent.parent(t);
        conjoinedNode = parent.getChild(nodeIndexes.get(i));
        String siblingLabel;

        //Remove all the nodes that are conjoined
        //with the selected noun (or are conjunctions, commas).
        //These can have labels NP, NN, ..., PRP for pronouns, CC, "," for commas, ":" for semi-colons
        for (int j = 0; j < parent.numChildren(); j++) {
            if (parent.getChild(j) == conjoinedNode)
                continue;
            siblingLabel = parent.getChild(j).label().toString();
            if (siblingLabel.matches("^[NCP,:S].*")) {
                parent.removeChild(j);
                j--;
            }
        }

        //if there is an trivial unary "NP -> NP",
        //remove the parent and put the child in its place
        if (parent.numChildren() == 1 && parent.getChild(0).label().equals("NP")) {
            int tmpIndex = gparent.indexOf(parent);
            gparent.removeChild(tmpIndex);
            gparent.addChild(tmpIndex, parent.getChild(0));
        }

        correctTense(conjoinedNode, gparent);
        addQuotationMarksIfNeeded(newQuestion.getIntermediateTree());

        if (GlobalProperties.getDebug())
            System.err.println("extractConjoinedNPs: " + newQuestion.getIntermediateTree().toString());
        if (GlobalProperties.getComputeFeatures())
            newQuestion.setFeatureValue("extractedFromConjoinedPhrases", 1.0); //old feature name
        if (GlobalProperties.getComputeFeatures())
            newQuestion.setFeatureValue("extractedFromConjoinedNPs", 1.0);
        extracted.add(newQuestion);
    }
}

From source file:edu.cmu.ark.SentenceSimplifier.java

License:Open Source License

/**
 * e.g., John and Mary like Bill.  -> John LIKES Bill.  Mary LIKES Bill.
 * John and I like Bill -> John LIKES Bill.  I LIKE Bill.
 * John and I are old. -> I IS old. John IS old.
 *//*w ww . j a va 2  s  . c  o m*/
private void correctTense(Tree subject, Tree clause) {
    int tmpIndex;
    //correct verb tense when modifying subjects
    for (Tree uncle : clause.getChildrenAsList()) {
        String newVerbPOS = null;
        Tree verbPreterminal = null;
        boolean needToModifyVerb = false;
        //if the node is a subject (i.e., its uncle is a VP), then check
        //to see if its tense needs to be changed
        String headPOS = subject.headPreTerminal(AnalysisUtilities.getInstance().getHeadFinder()).label()
                .toString();
        if (uncle.label().toString().equals("VP") && !headPOS.endsWith("S")) {
            verbPreterminal = uncle.headPreTerminal(AnalysisUtilities.getInstance().getHeadFinder());
            //original main verb was plural but the conjoined subject word is singular
            //e.g., John (and Mary) like Bill.  -> John like Bill.
            if ((verbPreterminal.label().toString().equals("VB")
                    || verbPreterminal.label().toString().equals("VBP"))) { //the parser confuses VBP with VB
                if (subject.yield().toString().equals("I") || subject.yield().toString().equals("you")) {
                    newVerbPOS = "VBP";
                } else {
                    newVerbPOS = "VBZ";
                }
                needToModifyVerb = true;
            } else if (verbPreterminal.label().toString().equals("VBD")) {
                newVerbPOS = "VBD";
                needToModifyVerb = true;
            }
        }
        //if needed, change the tense of the verb
        if (needToModifyVerb) {
            String verbLemma = AnalysisUtilities.getInstance().getLemma(
                    verbPreterminal.getChild(0).label().toString(), verbPreterminal.label().toString());
            String newVerb;
            //special cases
            if (verbLemma.equals("be") && newVerbPOS.equals("VBD")) {
                if (subject.label().toString().endsWith("S"))
                    newVerb = "were";
                else
                    newVerb = "was";
            } else if (verbLemma.equals("be") && subject.yield().toString().equals("I")
                    && newVerbPOS.equals("VBP")) {
                newVerb = "am";
            } else { //default
                newVerb = AnalysisUtilities.getInstance().getSurfaceForm(verbLemma, newVerbPOS);
            }
            tmpIndex = verbPreterminal.parent(uncle).indexOf(verbPreterminal);
            Tree verbParent = verbPreterminal.parent(uncle);
            verbParent.removeChild(tmpIndex);
            verbParent.addChild(tmpIndex,
                    AnalysisUtilities.getInstance().readTreeFromString("(" + newVerbPOS + " " + newVerb + ")"));
        }
    }
}

From source file:edu.cmu.ark.SentenceSimplifier.java

License:Open Source License

private void removeConjoinedSiblingsHelper(Tree copy, int childindex) {
    if (GlobalProperties.getDebug())
        System.err.println("removeConjoinedSiblingsHelper: " + copy.toString());
    Tree child = copy.getNodeNumber(childindex);
    Tree parent = child.parent(copy);
    Tree gparent = parent.parent(copy);//  w  w w  . ja v a 2  s.  co m

    int parentIdx = gparent.indexOf(parent);

    //By an annoying PTB convention, some verb phrase conjunctions 
    //can conjoin two verb preterminals under a VP,
    //rather than only allowing VP nodes to be conjoined.
    //e.g., John walked and played.
    //So, we add an extra VP node in between if necessary
    if (child.label().toString().startsWith("VB")) {
        gparent.removeChild(parentIdx);
        Tree newTree = factory.newTreeNode("VP", new ArrayList<Tree>());
        newTree.addChild(child);
        gparent.addChild(parentIdx, newTree);
    } else {
        gparent.setChild(parentIdx, child);
    }
}

From source file:elkfed.coref.features.pairs.FE_AppositiveParse.java

License:Apache License

public static Boolean getAppositivePrs(PairInstance inst) {

    // should be in the same sentence
    if (inst.getAnaphor().getSentId() != inst.getAntecedent().getSentId())
        return false;

    // exclude pairs where anaphor is an NE -- this might be a bad idea though..
    if (inst.getAnaphor().isEnamex())
        return false;

    if (inst.getAntecedent().isEnamex() && inst.getAnaphor().isEnamex()) {

        // exclude pairs of NE that have different type

        if (!(inst.getAntecedent().getEnamexType().equals(inst.getAnaphor().getEnamexType())))
            return false;

        // exclude pairs of LOC-ne
        if (inst.getAntecedent().getEnamexType().toLowerCase().startsWith("gpe"))
            return false;
        if (inst.getAntecedent().getEnamexType().toLowerCase().startsWith("loc"))
            return false;
    }//www  . j  a v a  2  s .  c o  m

    // should have not-null  maxnp-trees (otherwise -- problematic mentions)

    Tree sentenceTree = inst.getAnaphor().getSentenceTree();
    Tree AnaTree = inst.getAnaphor().getMaxNPParseTree();
    Tree AnteTree = inst.getAntecedent().getMaxNPParseTree();
    if (sentenceTree == null)
        return false;
    if (AnaTree == null)
        return false;
    if (AnteTree == null)
        return false;

    // the structure should be ( * (,) (ANA)) or ( * (,) (ANTE)) -- depends on the ordering, annotation, mention extraction etc

    if (AnteTree.parent(sentenceTree) == AnaTree) {
        Tree[] chlds = AnaTree.children();
        Boolean lastcomma = false;
        for (int i = 0; i < chlds.length && chlds[i] != AnteTree; i++) {
            lastcomma = false;
            if (chlds[i].value().equalsIgnoreCase(","))
                lastcomma = true;
        }
        return lastcomma;
    }
    if (AnaTree.parent(sentenceTree) == AnteTree) {

        Tree[] chlds = AnteTree.children();
        Boolean lastcomma = false;
        for (int i = 0; i < chlds.length && chlds[i] != AnaTree; i++) {
            lastcomma = false;
            if (chlds[i].value().equalsIgnoreCase(","))
                lastcomma = true;
        }
        return lastcomma;

    }

    return false;

}

From source file:elkfed.coref.features.pairs.FE_CCommand.java

License:Apache License

public static Boolean getCCommand(PairInstance inst) {

    // should be in the same sentence
    if (inst.getAnaphor().getSentId() != inst.getAntecedent().getSentId())
        return false;

    //Ana should not be reflexive or reciprocal pronoun
    if (inst.getAnaphor().getReflPronoun())
        return false;

    // should have not-null  maxnp-trees (otherwise -- problematic mentions)

    Tree sentenceTree = inst.getAnaphor().getSentenceTree();
    Tree AnaTree = inst.getAnaphor().getMaxNPParseTree();
    Tree AnteTree = inst.getAntecedent().getMaxNPParseTree();
    if (sentenceTree == null)
        return false;
    if (AnaTree == null)
        return false;
    if (AnteTree == null)
        return false;

    // should not dominate each other
    if (AnaTree.dominates(AnteTree))
        return false;
    if (AnteTree.dominates(AnaTree))
        return false;

    //the first branching node for ante should dominate ana (but not via S-node)
    AnteTree = AnteTree.parent(sentenceTree);
    while (AnteTree != null) {

        if (AnteTree.children().length > 1) {
            if (!AnteTree.dominates(AnaTree))
                return false;
            while (AnaTree != null && AnaTree != AnteTree) {
                if (AnaTree.value().toLowerCase().startsWith("s"))
                    return false;
                AnaTree = AnaTree.parent(sentenceTree);
            }/*from   ww w  . j a v a 2  s .  c  om*/
            return true;
        }
        AnteTree = AnteTree.parent(sentenceTree);
    }

    return false;
}

From source file:elkfed.coref.features.pairs.FE_Copula.java

License:Apache License

public static Boolean getCopula(PairInstance inst) {

    // should be in the same sentence
    if (inst.getAnaphor().getSentId() != inst.getAntecedent().getSentId()) {
        return false;
    }//from  ww  w  .  j  av a2  s.com

    // should have not-null  maxnp-trees (otherwise -- problematic mentions)

    Tree sentenceTree = inst.getAnaphor().getSentenceTree();
    Tree AnaTree = inst.getAnaphor().getMaxNPParseTree();
    Tree AnteTree = inst.getAntecedent().getMaxNPParseTree();
    if (sentenceTree == null) {
        return false;
    }
    if (AnaTree == null) {
        return false;
    }
    if (AnteTree == null) {
        return false;
    }

    // exclude "there is .." (ToDo: exclude other expletives!)

    if (inst.getAntecedent().getMarkableString().toLowerCase().matches(NONREF_NP)) {
        return false;
    }

    //exclude date and time

    if (inst.getAnaphor().getSemanticClass() == SemanticClass.TIME) {
        return false;
    }
    if (inst.getAnaphor().getSemanticClass() == SemanticClass.DATE) {
        return false;
    }
    if (inst.getAntecedent().getSemanticClass() == SemanticClass.TIME) {
        return false;
    }
    if (inst.getAntecedent().getSemanticClass() == SemanticClass.DATE) {
        return false;
    }

    // should be subj-obj of the same verb

    Tree vp = AnaTree.parent(sentenceTree);
    if (vp == null) {
        return false;
    }
    if (!vp.value().equalsIgnoreCase("vp")) {
        return false;
    }
    while (vp.parent(sentenceTree) != null && vp.parent(sentenceTree).value().equalsIgnoreCase("vp")) {
        vp = vp.parent(sentenceTree);
    }
    if (vp.parent(sentenceTree) == null) {
        return false;
    }

    Boolean foundante = false;
    Tree[] chldsup = vp.parent(sentenceTree).children();
    for (int i = 0; i < chldsup.length; i++) {
        if (chldsup[i] == AnteTree) {
            foundante = true;
        }
        if (chldsup[i] == vp && foundante == false) {
            return false;
        }
    }

    vp = AnaTree.parent(sentenceTree); // we do not want to go higher here -- "S is *ing O" fires otherwise

    // should not contain a modal verb
    Tree[] chlds = vp.children();
    for (int i = 0; i < chlds.length; i++) {
        if (chlds[i].value().equalsIgnoreCase("rb")) {
            return false;
        }
        if (chlds[i].value().equalsIgnoreCase("md")
                && chlds[i].getLeaves().get(0).value().toLowerCase().matches(MODAL_VERB)) {
            return false;
        }
    }

    // the verb should be one of the copula verbs

    for (int i = 0; i < chlds.length; i++) {

        if (chlds[i].value().equalsIgnoreCase("vbd") || chlds[i].value().equalsIgnoreCase("aux")
                || chlds[i].value().equalsIgnoreCase("vbn") || chlds[i].value().equalsIgnoreCase("vb")
                || chlds[i].value().equalsIgnoreCase("vbd") || chlds[i].value().equalsIgnoreCase("vbp")
                || chlds[i].value().equalsIgnoreCase("vbz") || chlds[i].value().equalsIgnoreCase("vbg")) {
            if (chlds[i].getLeaves().get(0).value().toLowerCase().matches(COPULA_VERB)) {
                /*
                System.out.println("Found positive copula verb (" 
                 +chlds[i].getLeaves().get(0).value() +
                ") for ("+
                inst.getAnaphor().getMarkableString()+
                "),("+
                inst.getAntecedent().getMarkableString()+
                ") ");
                */
                return true;
            }
        }
    }
    return false;
}