private void AppendHiddenWord(StringBuilder builder, HiddenWord currentWord, bool includeSolution)
        {
            //Replaced by OL of sentences
            //builder.AppendLine($@"<td width=""250"" class=""normal"">{currentWord.SentenceHidingWord}</td>");
            int    numberOfPrecedingEmptyCells = CombinedKeyIndex - currentWord.KeyIndex;
            string uppercaseCurrentWord        = currentWord.Word.ToUpperInvariant();

            for (int index = 0; index < CombinedLength; index++)
            {
                if (index < numberOfPrecedingEmptyCells) // cells before word
                {
                    AppendCell(builder, @"hollow", @"&nbsp;");
                    continue;
                }
                if ((CombinedKeyIndex + currentWord.LettersAfterIndex) < index) //cells after word
                {
                    AppendCell(builder, @"hollow", @"&nbsp;");
                    continue;
                }

                string letterInWord = "&nbsp;";
                if (includeSolution)
                {
                    letterInWord = uppercaseCurrentWord[index - numberOfPrecedingEmptyCells].ToString();
                }

                string classAttributes = "normal centered";
                if (index == CombinedKeyIndex)
                {
                    classAttributes = "bold centered";
                }
                AppendCell(builder, classAttributes, letterInWord);
            }
            builder.AppendLine("</tr>");
        }
 public void AddWord(HiddenWord hiddenWordToAdd)
 {
     _hiddenWords.Add(hiddenWordToAdd);
 }