What can children learn about morphology from reading for fun?

A key part of becoming a skilled reader is understanding how words are built — that is, how small parts of words that carry meaning come together to form words. For example, the word unhappy is made up of two parts: un- and happy, and the word unhappiness includes both of these parts as well as a third part, -ness. These meaningful parts are called morphemes, and each one contributes in a specific way to a word’s meaning.

Morphemes are important because knowing how they work helps us understand both familiar and unfamiliar words. For instance, you can probably make sense of words like yellowness and quickify, even if you’ve never heard or used them before. The fact that we can interpret new words like these so easily shows that we’ve developed knowledge about how morphemes work. But what we don’t fully understand is how this sensitivity to word structure is acquired in the first place. That’s what we set out to explore in this project. We analysed every word in 1,200 books popular among British children and young people aged 7–16 to assess how experience with these words might support the learning of morphemes. What we found was surprising!

Examples of the books included in our analysis.

Books are rich in structurally complex words…

Our analysis showed that nearly half of the distinct words in these books are made up of more than one morpheme. We also found that many of these words never appear on British television. The books we analysed were selected for their popularity rather than educational value, so it is striking that they turned out to be a far richer source of morpheme exposure than everyday spoken language.

… but these words rarely repeat

However, despite the high number of complex words in books, most of these words aren’t repeated often or found across multiple books. This means that while children are very likely to come across complex words as they read, they’re unlikely to encounter the same words again. As a result, they won’t have many opportunities to learn to recognise these words by sight. Instead, they’ll need to rely on their ability to break the words down into their individual morphemes. This highlights just how important morpheme knowledge is, even when children are simply reading for fun.

Examples of words made up of several morphemes found in popular children's books.

Few morphemes occur in many different words

Previous research shows that, in order to learn morphemes without formal and systematic instruction, we need to see them used in lots of different words. Take the prefix un- in words like unkind, unclean, and unafraid. You understand that it means “not” because it appears in many different words and always carries the same meaning. However, our analysis found that this is true for only about one third of the morphemes we examined. Most morphemes don’t appear in more than 300 different words, and only a small number of those words show up in many books. If that doesn’t sound particularly low, keep in mind that we looked at 1,200 books. No child will read that many, which means their actual exposure to most morphemes is likely much more limited.

Most morphemes are hard to find

Breaking complex words down into their morphemes can be tricky because the words’ internal structure isn’t always obvious. For example, the word deceive contains the prefix de-, but if you remove it, you’re left with ceive, which isn’t a word on its own. That’s because ceive comes from the Latin capere, meaning “to take” — a connection that only someone with strong knowledge of word origins might recognise. The same goes for a word like submit, which includes the prefix sub-, but where mit isn’t a meaningful word in modern English. Consider also words like dominance and tolerance — they include the suffix -ance, but the parts that come before it (domin, toler) don’t exist as standalone words in English.

These aren’t rare exceptions. Our analysis shows that children will struggle to identify the prefix in about half of all genuinely prefixed words, and the suffix in about a third of all genuinely suffixed words. This means the number of words that children can clearly recognise as complex — and use to learn something about the morphemes they contain — is much smaller than we might assume if we just count how many words in books include morphemes according to a dictionary.

Some words only appear complex

To make things even trickier, some words look like they’re made up of morphemes when they’re actually not. For example, the word deliver seems like it includes the prefix de-, but it doesn’t. It actually comes from the Latin liberare (“to free”) and has nothing to do with the word liver! The same goes for words like brother, army, or forty — they appear to contain suffixes like -er or -y because removing those endings leaves behind meaningful words like broth, arm, or fort. But in reality, there’s no meaningful relationship between brother and broth, or forty and fort — these are just spelling coincidences.

This kind of misleading structure — what we might call a “false alarm” — can confuse readers and make it harder to figure out what morphemes actually mean. While this doesn’t happen often with most affixes, it’s surprisingly common with a few. For example, we found 155 words in our books that look like they use the prefix e-, but only 25 really do. In other words, there’s a lot of noise and not much signal when it comes to figuring out what e- really means. Think about words like enervate, eloquent, and emigrate — they all contain the prefix e-, but it’s hard to pin down a consistent meaning for e- across them, isn’t it? Our research suggests that this uncertainty might stem from not having seen enough clear and consistent uses of e- to build a strong sense of its meaning.

Illustration of learning challenges associated with 14 common morphemes, highlighting how words that appear to contain these morphemes can be useful, irrelevant, or even misleading for learners.

Where does this leave us?

Summing up, our analysis shows that while reading does give children the opportunity to experience morphology in action, reading experience alone is unlikely to be enough for them to learn the meanings and functions of many individual morphemes. That’s because many morphemes appear in only a small number of words, require specialised knowledge to identify, or show up in misleading ways that can confuse learners.

These findings raise two important points. First, when we try to understand how morphemes are learned, we need to take the reader’s perspective into account. Just because a dictionary classifies something as a morpheme doesn’t mean a reader will recognise it as such — as our results show, many morphemes are not detectable from spelling alone.

Second, it might be time to rethink how we teach morphology. In English-speaking countries, morphology instruction in schools is often patchy and tends to focus on spelling rules or the most common prefixes and suffixes. The assumption is that the most frequently used morphemes are also the most useful to teach. But our findings suggest it might be worth focusing instead on morphemes that are hard to spot, or that often appear in misleading contexts (i.e., the false alarms). These are the morphemes children are least likely to learn through reading alone — and the ones that may benefit most from explicit instruction.

Further reading

If you’d like to learn more about this research, you can read and download the full article for free:

Korochkina, M., & Rastle, K. (2025). Morphology in children’s books, and what it means for learning. npj Science of Learning, 10:22. https://doi.org/10.1038/s41539-025-00313-6.

Data and code at https://osf.io/vab95/.

It offers an accessible and engaging discussion of our findings and conclusions on how children learn morphemes, as well as what this means for both language research and the design of effective morphology instruction.