Spaced Repetition: The Science Behind Vocabulary Retention

You've probably had this experience: you learn 20 Vietnamese words, feel great, and then forget 15 of them by next week. Spaced repetition fixes this. ## The Forgetting Curve In 1885, psychologist Hermann Ebbinghaus discovered that we forget roughly 70% of new information within 24 hours — unless we actively review it. Each review slows the forgetting curve, making the memory more durable. ## How Spaced Repetition Works Instead of reviewing everything every day (exhausting and inefficient), you review each item at increasing intervals: 1. Learn a new word today 2. Review tomorrow (1 day later) 3. Review in 3 days 4. Review in 7 days 5. Review in 14 days 6. Review in 30 days If you get it right each time, the intervals grow. If you forget, the word resets to shorter intervals. This means you spend the most time on words you find hardest. ## Why It's Perfect for Vietnamese Vietnamese vocabulary includes tone information. "Bán" (sell) and "bàn" (table) are different words. Spaced repetition forces you to recall the complete word — including its tone — at each review. Over time, the correct tone becomes automatic. ## WELE + Spaced Repetition WELE's vocabulary review system uses spaced repetition algorithms. Words you encounter in dictation practice are automatically scheduled for review at optimal intervals. The combination of contextual learning (dictation) and systematic review (spaced repetition) is extremely effective. ## DIY Approach If you want to supplement WELE's system, use Anki (free flashcard app) with these rules: - Add words from your WELE dictation errors - Include audio on each card (hear the word, not just read it) - Always include full diacritics - Keep cards simple: one word or phrase per card - Review daily — 5 minutes is enough The combination of WELE dictation for learning words in context and spaced repetition for retaining them is the fastest path to a large, usable Vietnamese vocabulary.