If you want to review the alphabet, first, you need to make sure you have learned at least three letters.
Then, you have to:
1. Go to the "Tools" tab.
2. Tap on "Review".
3. Tap the "Alphabet" button.
4. Tap the smaller "Alphabet" button.
5. Select the letters you want to review (minimum 3).
6. Tap on the "Review" button.
What is a Review?
How do I review what I have learned?
How do I review the reading rules I have learned?