Play method for WordUp

Play.cs

private void Play(GameTime gameTime)
        {
                // Allows user to enter words
                KeyboardState keyboard = Keyboard.GetState();
                char pressedChar = KeyboardProcessor.GetLetter(keyboard);

                if (pressedChar != ' ')
                {
                    // Check whether the letter is one of the falling ones
                    if (currentWord.Contains(pressedChar.ToString()))
                    {

                        keyPressSound.Play();
                        typedLetters.Add(pressedChar);
                    }
                    else
                    {
                        errorSound.Play();
                        Debug.WriteLine("Current word: {0}", currentWord);
                        Debug.WriteLine("Current word doesn't have {0}", pressedChar);
                    }
                }
                // User presses enter, check if word exists in dictionary
                if (typedLetters.Count > 0 && keyboard.IsKeyDown(Keys.Enter))
                {
                    enterDown = true;
                }
                if (enterDown && keyboard.IsKeyUp(Keys.Enter))
                {
                    string word = "";

                    foreach (char c in typedLetters)
                    {
                        word += c;
                    }
                    Debug.Write("Checking the following word: {0} ...", word);

                    // Check if word exists in dictionary
                    if (wordDictionary.ContainsKey(word))
                    {
                        Debug.WriteLine("found.");
                        // 1. Remove word from word dictionary
                        wordDictionary.Remove(word);
                        // 2. Update score
                        score += ScoreTools.GetWordScore(word);
                        Debug.WriteLine("Total score: {0}", score);
                        wordSuccessSound.Play();
                        // 3. Clear current letters
                        clearLetters();
                    }
                    else
                    {
                        // Word not found in dictionary, play error sound
                        errorSound.Play();
                        // Clear typed letters 
                        typedLetters.Clear();
                        Debug.WriteLine("not found.");
                    }
                    enterDown = false;
                }

                // Remove one letter with backspace
                if (keyboard.IsKeyDown(Keys.Back))
                {
                    backspaceDown = true;
                }
                if (backspaceDown && (typedLetters.Count > 0) && !shiftBackspaceDown)
                {
                    if (keyboard.IsKeyUp(Keys.Back))
                    {
                        letterDeleteSound.Play();
                        typedLetters.RemoveAt(typedLetters.Count - 1);
                        backspaceDown = false;
                    }
                }

                // Left shift + backspace pressed to delete entire typed word
                if (keyboard.IsKeyDown(Keys.LeftShift) && keyboard.IsKeyDown(Keys.Back))
                {
                    shiftBackspaceDown = true;
                }
                if (shiftBackspaceDown && (typedLetters.Count > 0))
                {
                    if (keyboard.IsKeyUp(Keys.Back) || keyboard.IsKeyUp(Keys.LeftShift))
                    {
                        wordDeleteSound.Play();
                        typedLetters.Clear();
                        shiftBackspaceDown = false;
                    }
                }

                // Allows user to change the speed of the game via keyboard

                if (keyboard.IsKeyDown(Keys.Up))
                {
                    keyDownPressed = true;
                }

                if (keyDownPressed == true)
                {

                    if (keyboard.IsKeyUp(Keys.Up))
                    {
                        if (gameSpeed != GameSpeed.ULTRA_FAST)
                        {
                            gameSpeed++;

                        }
                        else
                        {
                            gameSpeed = GameSpeed.VERY_SLOW;
                        }

                        foreach (Letter letter in wordLetterList)
                        {
                            letter.Speed = gameSpeed;
                        }
                        keyDownPressed = false;
                        Debug.WriteLine("Game speed changed to " + gameSpeed.ToString());
                    }
                }


                foreach (Letter letter in wordLetterList)
                {

                    if (letter.OffScreen)
                    {
                        offScreen = true;
                    }
                    letter.Update(gameTime);
                }

                // Check if letters have gone off screen
                if (offScreen)
                {
                    clearLetters();
                    offScreen = false;


                    // Life lost

                    if (livesList.Count > 0)
                    {
                        livesList.RemoveAt(livesList.Count - 1);
                        lifeLostSound.Play();
                    }
                    // All lives lost, game over
                    else
                    {
                        currentGameState = GameState.GameOver;
                    }
              }
        }