MarkovText.Markov.readWordGroups C# (CSharp) Method

        private void readWordGroups()
        {
            statusForm.status = "building data structure...";
            string key;
            for (int i = 0; i < (words.Count - k - 1); i++)
            {
                key = buildKey(i);
                //System.Windows.Forms.MessageBox.Show("Adding " + word + " to key " + key + ".");
                if (wordGroups.ContainsKey(key))
                {
                    wordGroups[key].Add(words[i+k]);
                    continue;
                }
                wordGroups.Add(key, new List<string>());
                wordGroups[key].Add(words[i + k]);
            }
        }