code: @Nullable
    private String getNumAgreedPosTag(String leftPosTag, String rightPosTag, boolean leftNv) {
      String agreedPosTag = null;
      
      if( leftPosTag.contains(":p:") && SING_REGEX_F.matcher(rightPosTag).find()
          || SING_REGEX_F.matcher(leftPosTag).find() && rightPosTag.contains(":p:")) {
        String leftConj = PosTagHelper.getConj(leftPosTag);
        if( leftConj != null && leftConj.equals(PosTagHelper.getConj(rightPosTag)) ) {
          agreedPosTag = leftPosTag;
        }
      }
      return agreedPosTag;
    }
docs: right part is numr