Spaced repetition flashcards work for English vocabulary because they combine two things at the same time: a single word on the front of a card, and a return visit at a specific interval that depends on how easily you recalled it. Each time you try to produce the meaning before you see it, the brain has to retrieve the answer rather than simply recognize it, and that retrieval is what strengthens the memory. A disclosed schedule then stretches the gap between reviews from one day to two days to four days for words you recall easily, and resets a forgotten word to the very next day. The result is a predictable rhythm of short, focused sessions where every word you see is one you are due to forget, rather than one you already know. The eight adjectives covered in this deck — lucid, prudent, resilient, concise, impartial, fragile, verbose, and biased — are the eight literal word keys the deck tests, each cross-checked against a Princeton WordNet 3.1 entry and a dedicated Cambridge Dictionary page. Each card cross-references a Princeton WordNet 3.1 entry with a dedicated Cambridge Dictionary page, so the spelling and the displayed ordinary sense are auditable reference data rather than invented examples.
Why a Schedule Plus Recall Beats Passive Rereading
The core claim behind spaced repetition is straightforward: a word you have to retrieve from memory sticks better than a word you simply read over. Re-reading a list creates familiarity, but familiarity can hide the fact that you would not be able to produce the word unprompted. Flashcards flip that around by hiding the meaning until you have tried to recall it. The schedule then decides when each card returns, based on the last grade you gave yourself. A card you recall easily is shown less often; a card you forget is shown the very next day.
For English vocabulary this matters because the language has many high-utility words that look familiar but rarely get used in speech or writing. Adjectives such as concise and verbose are easy to skip past in a textbook because the eye recognizes them, yet actively producing them in a sentence is harder than most learners expect. Forcing the recall a single time, on a card, is a small step that compounds across dozens of words, and a transparent schedule lets you predict exactly when each card will return.
What the Eight Adjective Cards Cover
The deck contains exactly eight adjectives, each on its own card. Every spelling and every displayed meaning is cross-checked against Princeton WordNet 3.1 and a dedicated Cambridge Dictionary page, so you can audit each card against a real reference rather than trust an invented list. The short meanings on the back of each card are paraphrases of overlapping senses, not copied dictionary examples, and they are the literal strings that the deck tests.
| Word | Displayed meaning |
|---|---|
| lucid | clearly expressed and easy to understand |
| prudent | careful and avoiding unnecessary risks |
| resilient | able to recover successfully after difficulty |
| concise | short and clear without unnecessary words |
| impartial | not supporting either side in a dispute |
| fragile | easily damaged or broken |
| verbose | using more words than necessary |
| biased | showing unreasonable preference based on personal opinions |
If you would like to inspect the underlying reference pages, the Cambridge Dictionary entry for biased and the Cambridge Dictionary entry for concise show how each displayed sense is grounded in a published dictionary.
Run a Review Session Step by Step
The session flow is the same on every visit: see a word, try to remember its meaning, reveal the paraphrase, then grade yourself honestly. The full step-by-step is below.
- Open the Vocabulary Flashcards (Spaced Repetition) page and let the first due card load.
- Say or think of the meaning of the adjective shown on the front of the card. Do not skip this step, because the retrieval is the point.
- Press Space or Enter to reveal the source-grounded paraphrase on the back.
- If you recalled the meaning, press G for Got it. The card moves to the next box, up to box 3, and is due again later.
- If you missed or hesitated, press A for Again. The card returns to box 1 and is due the next day.
- Continue until every due card in the session has been graded once. Buttons give the same path for touch and pointer input.
- Close the tab or come back the next day. When you return, any card whose due day has passed will appear again, and progress stays where you left it in this browser.
Only an explicit Again or Got it choice changes progress. A due date never grades a card on its own, and a card you have not yet revealed cannot be graded. One due card can be graded once per session, and an attempt to grade it again is rejected. When every currently due card has been handled, the summary shows cards reviewed, Got it choices, Again choices, and points.
How the Three-Box Modified-Leitner Schedule Works
The deck uses a disclosed three-box Modified-Leitner schedule. Every card begins in box 1. When you grade a card, its next-due date is recalculated, and only your grade can change that date. The MIT 6.031 reading on Modified-Leitner flashcards and the University of York summary of the Leitner System both confirm the core direction: correct recall promotes a card to a less frequent box, and incorrect recall returns it to the first box for more frequent review.
| Box | Due after | On Got it | On Again |
|---|---|---|---|
| 1 | 1 day | Move to box 2 | Stay in box 1 |
| 2 | 2 days | Move to box 3 | Return to box 1 |
| 3 | 4 days | Stay in box 3 | Return to box 1 |
To see the arithmetic at work, walk through one card. A box-1 card recalled on day 10 moves to box 2 and becomes due on day 12 (10 + 2 = 12). Recalled again on day 12, it moves to box 3 and is due on day 16 (12 + 4 = 16). Marked Again on day 16, it returns to box 1 and is due on day 17 (16 + 1 = 17). The schedule is the same every time, regardless of which adjective you are reviewing.
Box numbers and next-due days are stored in this browser under a single versioned localStorage key. The stored payload contains only the eight card IDs, their box numbers, and their next-due integer days, so nothing leaves your device. If browser storage is denied, by a privacy setting, policy, quota, or private mode, the deck continues with an in-memory deck for the current tab and tells you so. Invalid JSON, a wrong schema version, missing cards, duplicate IDs, invalid boxes, or invalid days is discarded in favour of a clean local deck. Restart resets all eight local cards to box 1 so the schedule can be replayed from a known state.
Why a Small Fixed Deck Is Useful for Building a Habit
An eight-card deck is too small to grow your vocabulary the way a thousand-card deck might, and the tool is explicit about that. What a small fixed deck does well is make the schedule visible. With only eight cards, you can see the whole pipeline at once: which cards are in box 1, which have stretched out to box 3, which are due tomorrow, and which have just been reset. That visibility is what turns spaced repetition from a vague promise into a habit you can audit after every session.
For deeper coverage of how fixed intervals compare with adaptive ones, the Adaptive vs Fixed Flashcard Intervals guide walks through the same Modified-Leitner model in more depth and explains why a transparent fixed schedule is often the right starting point for a new deck.
What This Exercise Does and Does Not Measure
It is worth stating plainly what the deck is and is not. It is a private recall game with auditable words and scheduling rules. It is not a vocabulary size estimate, a CEFR placement score, a fluency rating, an IQ measure, a memory assessment, or any kind of educational or clinical evaluation. Eight cards cannot evaluate school readiness, employment fitness, a learning condition, or treatment progress, and the deck never claims to. Each Got it is worth 100 recreational points; no proficiency level, vocabulary size, grade, CEFR band, percentile, or educational placement is inferred from those points.
The session summary at the end of each round is a record of how you graded yourself, not a verdict on your English. For formal language guidance or accessibility support, an appropriate qualified educational service is the right path. Treated as a small, transparent recall exercise, the deck is a useful place to feel how spaced repetition actually behaves before you scale it up to a larger personal vocabulary list.
Related reading: Vocabulary Quiz: How the Adaptive Difficulty Works.