Steven Fry’s recent documentary series, Fry’s Planet Word, included a segment where Jean Berko-Gleason, who published a landmark research paper way back in 1958, ran the same test with a modern-day child. A couple of people that I spoke to about the programme mentioned that they weren’t quite clear exactly what the point of the test was. So I thought for today’s blog it might be interesting to explore this classic study, its findings, and what it tells us about children’s language.
The test goes something like this. The researcher shows the picture a child of a funny-looking creature and says “this is a wug“. The word wug, like the creature itself, is completely made-up; invented for the purposes of the experiment. The experimenter then brings out a new picture that shows two of these creatures and says to the child “so these are two…”. Even young children (the youngest in this study were 4 years old) are generally able to correctly answer “wugs”.
What’s the point of this study? One of the most fundamental rules of English is that to make the plural of a noun (which, for our purposes, we can think of as simply a word that names a person, animal or thing) we add an -s. Whilst, from an adult perspective, this rule seems almost too obvious to be worth discussing, it’s actually quite remarkable how quickly children pick this up. No parent goes around saying “now Johnny, to form the plural of a noun, simply add -s to the singular form”; not that children would understand if they did. Somehow, children work this out all by themselves, many years before they are taught about “nouns” and “plurals” (indeed, many people are never taught explicitly about these things).
But what’s the point of all this wug business? Why didn’t Berko (as she was back then) simply ask children for the plural of cat, dog, chair, table etc? The reason is that if a child is able to say “two cats”, this doesn’t actually provide any evidence that she’s learned the ‘add -s’ rule at all. She may simply have learned, by listening to adults, that cats is the word we use when there’s more than one. In contrast, the child cannot possibly have learned the plural form wugs by listening to adults, as we can say with complete confidence that no adult has ever uttered this word in her presence; it was invented solely for the purposes of the experiment. So if the child can correctly produce wugs, we can tell that she has – somehow -arrived at the ‘add -s‘ rule.
As you have probably noticed by listening to your own children, once they have acquired this rule, they tend to go overboard, adding -s to all kinds of words that actually have different plural forms (e.g., childs, foots and mouses instead of children, feet and mice). These types of errors have been studied extensively in child language research, and it is no exaggeration to say that they could easily fill a book on their own. However, we’ll save these for another blog, as today I want to focus on errors where children go underboard, failing to add -s in cases where they should do, despite the fact that they seem to know the rule perfectly well.
At the point where children are quite happily adding -s to words like cat, dog, chair and table, they systematically fail to do so for words like box, horse, dress and lace. In fact, even four-year olds, most of whom will have acquired this rule somewhere between one and two years earlier, fall down on these words over half of the time. That is, more often that not, they say two box, two horse, two dress or two lace. What do these words have in common? The irregular nature of English spelling hides the fact that all of them already end in an -s sound in singular form (a more regular language might spell them boks, hors, drehs and laes). But four-year-olds don’t know or care about adult spellings; to them, all these words already end in -s. And since they already end in -s, there’s no need to add another one. When you think about it, this point of view is pretty logical in its own way, it just happens to be one that is not shared by adults.
Whilst errors where children add an extra -s (like childs or foots) stick out like a sore thumb, errors where children miss off an -s (two boxs) tend to slip under the radar (possibly because, at some level, hearing the -s tricks us into thinking that a plural form was actually produced). But now you’ve read this, you’ll hear them turning up in loads of different place.