How to Use Spaced Repetition to Remember English Vocabulary

Published on
October 13, 2020
Updated on
October 16, 2020
min read
Written by
Ramsay Lewis

Unless you have a photographic memory, you need to be exposed to new words multiple times to remember them. In this guide, we’ll look at how to use Spaced Repetition to learn vocabulary in the most effective way.

How to Use Spaced Repetition to Remember English Vocabulary

If you’ve ever learned a language, you’ve probably had this experience: you’re reading a menu, listening to a podcast, or watching a film and you see a word that sparks a vague recognition. 

But what does it mean again?

I’ve said that developing listening skills is probably where most English learners should focus the majority of their study time. Building vocabulary is an important part of that. 

In a previous article, I suggested 5 strategies to remember English vocabulary that are actually effective. The first strategy I talked about was spaced repetition. In this article, I want to elaborate a bit on that. I want to explain what it is, why it works, and give you some more details about how to use it. 

Learning English vocabulary is difficult

Learning English vocabulary really is difficult. 

Part of the reason for that is because English has been influenced by so many other languages. While the majority of the English words we use these days come from Latin (especially through French) origins, the core of English is Germanic. Add on to that the many words we stole (perhaps “borrowed”) from other languages (Dutch, Arabic, Welsh, Hebrew, Greek), and English can really feel like a mishmash

But not only that, the spelling, pronunciation, word choice, and even grammar preferences vary by region. Many words that are spelt differently sound the same (“bare” and “bear”), and many words that are spelt similarly are pronounced differently (“read” and “read”, “bow” and “bow”). 

My students, without fail, have a particularly difficult time with the “-ough” words. “Cough” rhymes with “off” but “through” is pronounced the same as “threw”, while “though” is somehow pronounced in a way that rhymes with “toe”. And “tough” rhymes with “stuff”. And somehow “hiccough” is different from all of those.

I’ll tell you what I tell my students: there’s no easy rule to explain it. You just have to memorise the words and how to pronounce them. Spaced repetition is one way to memorise those words efficiently. 

What is spaced repetition?

Spaced repetition is a way to repeat information so that you remember it effectively. Spaced repetition has two parts: repetition and spacing. 


Repetition is a memorisation strategy as old as the hills. As the ancient Romans have said, Repetitio mater studiorum est, or, “Repetition is the mother of all learning”. 

The idea is that the more you repeat something, the better you learn it. 


The spacing effect refers to the observation that the learning that occurs from repetition is more effective when it is spaced out over time. Rather than repeatedly studying a word 100 times in the same day, a person would learn better if they repeated it 10 times a day for 10 days. 

Hermann Ebbinghaus did some of the first research on memory and forgetting. Ebbinghaus observed what I’m sure we all know: that the more time that passes, the more we forget. In a series of self-experiments, Ebbinghaus plotted what has come to be known as the “forgetting curve”.

The forgetting curve
The forgetting curve

It was Ebbinghaus that also first noticed the phenomenon of the spacing effect. 

He found that the most effective learning happens when the interval between repetitions is increased over time. So when a word is new, you would have to repeat it quite frequently to remember it. But the more you’ve seen it, the less frequently you need to repeat it.

In other words, you can reduce the amount of “forgetting” by spacing repetitions out. 

Does spaced repetition work?

Yes, there’s lots of research that has demonstrated that using spaced repetition leads to much more effective learning than other forms of studying. 

For example, one research team conducted a longitudinal study of a group of participants learning a new language over 9 years. They found that both increasing the number of repetitions and increasing the length between study intervals improved retention and memory. 

These same researchers further demonstrated that the optimal spacing interval for repetition is the maximum amount of time possible before the information is forgotten. 

To translate this into plain English, you have the best chance of remembering something if you see it again just before you would have forgotten it.

More recent studies have found that spacing repetition actually changes how the brain is wired. When repetition is spaced out more than an hour, brain connections are enhanced and the information is more likely to be stored in long-term memory. 

One research team reviewed over 800 studies on the effects of spaced repetition. They found that over 96% of the studies provided evidence that spaced repetition led to significantly improved learning outcomes. 

It’s now largely acknowledged that spaced repetition is one of the most effective ways to learn new information.

How can I use Spaced Repetition to remember words?

Great, so how can you use it? There are a few ways.

With paper flashcards 

One low-tech way is to create a spaced repetition system using flashcards. For example, you might choose to use the Leitner system. Here’s how you can do it. 

  1. First, create flashcards for the words you’d like to learn. At Leonardo English, we make this easy for you. Members have access to a list of target vocabulary for every episode of the English Learning for Curious Minds podcast. You can use this list to get you started on your flashcards.
  2. Then, group the flashcards by how well you know them. Make several groups—as many as you like. You might start with 3. Make the first group your group of cards you don’t know very well, the second group should be the cards you kind of know, and the third group can be those you feel like you’ve mastered.
  3. Go through the groups, testing yourself on the vocabulary. When you test yourself and correctly remember the word, move the card up one group. If you get a card wrong, put it back in the first group.
  4. Study the first group most often. These are the cards you don’t know very well. You can study the second group a bit less often, and the third group even less often than that. The idea is that you study those cards you don’t know more often than those you do. 

Check out this video to see what it looks like in practice. The video creator uses 7 groups instead of 3.

Spaced repetition flashcard applications

If you’re looking for something a little more intuitive to set up, there’s a bunch of applications that do all the work for you. Try out a few and see which you like best. 


Anki is probably the most famous spaced repetition flashcard system. It’s kind of an open-sourced hacker project and is available for free. 

I used to use Anki a lot, and it’s great. It’s not flashy and doesn’t have lots of features, but it’s easy to use. For each flashcard, you rate how well you know the word from “1” to “5”. Words you rate lower will repeat more often. You can make your own flashcard or find some made by others.


Brainscape is like an upgraded version of Anki. It works the same way: you can make your own flashcards or find those made by others. For each flashcard, you rank how well you knew the card from “1” to “5”. The lower you rate the card, the more often it repeats. 

Brainscape is free to make your own flashcards or find those from other people, but you can also subscribe for access to their “verified classes” which they’ve carefully curated. I currently use Brainscape much more than Anki. 

They have a “Vocabulary Builder” deck that includes over 800 difficult but useful words as well as prefixes and suffixes. You can also access decks made by other English learners.


This is another spaced repetition app. Whereas Anki and Brainscape can be used for anything, Memrise was designed especially for language learners. 

Another difference is that Memrise has several courses that they have pre-designed. That’s good if you want an app that has a curriculum, but it’s not great if you just want to be able to keep track of the words you’re learning elsewhere. 

Memrise is free to start, but you can subscribe for more languages and features. 

There are lots of others, but those will give you a taste for what they’re like. You can start for free on any of them and see if you like them. 

Importance of large amounts of comprehensible input

I should say here that while spaced repetition may be an especially effective way to remember information, it may not be—by itself—the most effective way to learn a language.

Learning English is, of course, more than simply memorising a bunch of words. You need to actually be exposed to language to learn it. 

As Alastair explained in his recent blog post, comprehensible input—exposure to language that you can understand—is essential to learning English. He details 11 ways that listening to podcasts with a transcript can help you listen, speak, read, and even learn vocabulary. 

But comprehensible input and spaced repetition can go together. 

Comprehensible input provides context, gives you language models, and helps to make sure you don’t get bored with your lessons. It can provide you with exposure to new words that you might want to learn. Spaced repetition can help make sure you don’t forget what you learned. 

So yes, spaced repetition is important. But I wouldn’t recommend trying to learn English with just a set of flashcards. Instead, use spaced repetition as one part of your English learning study programme

How Leonardo English can help

If you’re interested in spaced repetition, here’s how Leonardo English can help.

  1. Use the podcasts to find new words. Members can access a list of key vocabulary with each episode to make finding new words, and their definitions, convenient for you. 
  2. Attend monthly meetups. Leonardo English members are invited to monthly members-only sessions (the most recent one was a debate on the British Monarchy!). These are a great opportunity for you to get exposed to new words.
  3. Read the blogs. Your friends writing the blog at Leonardo English do their best to include expressions and idioms you might not know. Record these in your favourite spaced repetition system. 
  4. Request an episode on a topic that interests you. Alastair invites members to submit suggestions for future episode topics. If you want to learn some vocabulary on a particular topic, consider suggesting that topic for a podcast episode.

Build spaced repetition into your study

Spaced repetition is one of the most effective ways to remember new words.

Build it into your English study programme by keeping track of the new words you learn in your other study activities: as you listen to English, read in English, or talk with others in English

Then, make those words into flashcards—either paper ones or digital ones. Then go through them, studying the ones you know best less often. Focus on the ones you don’t know well. 

Spaced repetition is that easy. By doing it, you’ll be using one of the most effective learning techniques to expand your vocabulary and actually remember what you learn. 


Bahrick, H. P., Bahrick, L. E., Bahrick, A. S., & Bahrick, P. E. (1993). Maintenance of foreign language vocabulary and the spacing effect. Psychological Science, 4(5), 316-321.

Bahrick, H. P., & Phelps, E. (1987). Retention of Spanish vocabulary over 8 years. Journal of Experimental Psychology: Learning, Memory, and Cognition, 13, 344–349.

Cepeda, N., Pashler, H., Vul, E., Wixted, J., & Rohrer, D. (2006). Distributed practice in verbal recall tasks: A review and quantitative synthesis. Psychological Bulletin, 132(3), 354-380.

Kramár, E. A., Babayan, A. H., Gavin, C. F., Cox, C. D., Jafari, M., Gall, C. M., ... & Lynch, G. (2012). Synaptic evidence for the efficacy of spaced learning. Proceedings of the National Academy of Sciences, 109(13), 5121-5126.

Sisti, H. M., Glass, A. L., & Shors, T. J. (2007). Neurogenesis and the spacing effect: learning over time enhances memory and the survival of new neurons.Learning & memory, 14(5), 368-375.