If you want to review the words or sentences that are learned, you need to:
1. Go to the "Tools" tab.
2. Tap on "Review".
3. Choose what you want to review: Words or Sentences.
4. Tap on the "Learned" tab.
5. Choose the topics/ subtopics you want to review.
6. Tap the "Review" button.
What is a Review?
Why is the Review empty?
How do I know I have learned a word or sentence?