/** Called by {@link AbstractPOSTagger#processAux()}. */
  protected List<Pair<String, StringFeatureVector>> tag() {
    List<Pair<String, StringFeatureVector>> insts =
        new ArrayList<Pair<String, StringFeatureVector>>();
    DEPNode node;

    for (i_input = 1; i_input < t_size; i_input++) {
      if (!applyRules()) {
        node = d_tree.get(i_input);
        node.pos = getLabel(insts);
      }
    }

    return insts;
  }