CheckWordIsValid

        private static bool CheckWordIsValid(string Word, List<string> AllowedWords)
        {
            bool ValidWord = false;
            int Count = 0;
            while (Count < AllowedWords.Count && !ValidWord)
            {
                if (AllowedWords[Count] == Word)
                {
                    ValidWord = true;
                }
                Count++;
            }
            return ValidWord;
        }

The code starts by setting the variable ValidWord to false and the variable count to 0. The next line says while the count is less than the total number of allowed words & not a valid word then it sees if the word is in the allowed words and if it is then the count is incremented by 1, else it will return ValidWord.