What is spaced repetition and why does it work for vocabulary?

Spaced repetition means reviewing information at increasing intervals — right before you are about to forget it. It is the most consistently proven memory technique in learning research, going back to Ebbinghaus's forgetting-curve experiments in 1885.

The forgetting curve

After learning a new word you lose roughly half of it within a day and most of it within a week — unless you review. Each well-timed review flattens the curve: the interval before the next forgetting point gets longer. Review at 1 day, then 3, then 7, then 21, and the word moves into long-term memory with a handful of repetitions instead of dozens.

Why context multiplies the effect

Classic flashcards pair a word with a definition. Your memory works better with scenes: a word met in a Netflix subtitle or a real meeting comes with sound, situation and emotion attached. That is why Diction Flow stores every saved word with its original sentence and shows that context at review time.

How to use it in practice

1. Capture words while watching or in meetings — one click, no interruption.
2. Open your reviews daily; a session takes 5–10 minutes.
3. Rate honestly — the scheduler adapts intervals to each word's difficulty.
4. Take a weekly quiz to force active recall, the strongest memory signal.

Frequently asked questions

How many new words a day is realistic? 10–20 saved words a day is sustainable. More than that and reviews pile up.

Is spaced repetition enough on its own? No — it consolidates what you meet. Keep watching, reading and speaking; the repetition system is the glue, not the input.

Why not just re-watch the episode? Re-watching helps but repeats everything equally. Spaced repetition targets exactly the words you personally are about to forget.