“What’s a wug?” is a question people often ask me when they hear that I developed the Wug Test. A wug is a mythical little creature that looks rather like a bird. It’s included in a series of pictures I drew for a study of kids’ acquisition of English. We wanted to know if children know more about language than just the things they’ve heard from others. For instance, do preschoolers “know” how to make a plural? Adults do: if your friend says he had an “abdominoplasty” and you’ve never heard the word before you still know what two of them are called. Adults know that to make a plural you add some form of -s to the word.
To find out if kids have the same sort of knowledge we needed to use natural-sounding words that they didn’t already know. If we used real words like “dog,” they might know the plural “dogs,” but this could be an imitation of what they heard from adults. So I invented the little animal called a “wug,” a name that we could be sure they never heard before. We showed them pictures of a wug, and said “This is a wug.” Then we showed them another picture and said, “Now there’s another one. There are two of them. There are two….??” To our delight, even preschoolers could add the plural ending and tell us that there were two “wugs.” We used this invented word method to check kids’ knowledge of plurals, possessives, verb tenses, and a variety of other important features of English and found that by the age of 4 they could provide all the most common forms.
Children learn how to make regular plurals and past tenses before the irregular ones, and sometimes we can see that they have this linguistic knowledge by the kinds of “mistakes” they make. So the next time your 4-year-old friend says “I falled down and hurted myself,” you can be sorry for the booboo, but happy to know that the little guy has knowledge about some basics of the English language.