Beyond Just ‘Ma’ or ‘Da’: How Kids Learn to Speak Like Adults

Anyone who has ever spent time with toddlers has noticed that kids do some very inventive things with speech, such as regularizing irregular verbs (“go-ed,” “swimmed”) or misunderstanding that “dog” applies to all furry four-legged friends and not just the one at home. It can seem overwhelmingly difficult to imagine the process that underlies how children learn how to speak.

A long history 

The interest in how children acquire language goes back much farther than you might think. The ancient Greek historian Herodotus records what is probably the first child-language experiment performed in antiquity, although the babies’ welfare was certainly not the primary motivation. 

Instead, an Egyptian pharaoh set out to prove the superiority of his people by showing that the Egyptian language would emerge spontaneously as the primordial language from babies who were kept away from any type of language exposure. He commanded a local goatherder to take on the role of primary investigator, raising two babies in silence among his herds.

While certainly not so great an experience for the babies, it also turned out not so great for the pharaoh, because their first word was reportedly “bekos,” which was not an Egyptian word but a Phrygian word meaning “bread.” The Phrygians were another powerful empire in what was at the time western Anatolia.

Though this ancient experiment was not about language acquisition per se, it is often discussed by linguists as support for one of the leading theories about how children learn language so quickly early in life, known as nativism or innatism. In other words, nativism is the idea that children’s ability to speak emerges as a matter of biology, rather than any “learning” like we need for other higher skills such as reading and math. After all, how many people remember being introduced to the underlying grammatical rules of their language before they went to elementary school, and yet most 4-year-olds are very accomplished at talking in complete sentences.

Linguistic landmarks in infancy

Even before they hit the year-old mark, babies have a remarkable ability to communicate with adults by babbling even just a few vowels and consonants. “Ba,” “ma,” and “da” may not sound like much, but they sure seem to send a clear enough message, like “Get me my bottle!” or “Ma, get over here.”

Looking at research on child language acquisition, these early pseudo-words do seem to mean much more than they might appear to on the surface. They represent not simply a name for objects in their vicinity but attempts to converse about what they want those objects to be doing. 

Between 9 and 18 months, with only about a 50 word-vocabulary and no understanding of the underlying syntactic structure of their language, babies have to be circumspect in picking out which word will best get what they need at the moment. This first stage of sentence production is known as the holophrastic or one-word stage and marks the beginning of the emergence of what linguists call a child’s propensity for syntax (in other words, the rules that create sentences). While the exact age when babies start saying words can vary quite a bit, the stages of sentence acquisition they go through are pretty much the same despite being earlier or later for some.

As they get toward 18 to 24 months, young toddlers are starting to put two-word mini-sentences together, saying things like “Mama go,” or “No baba” (meaning “no bottle”). This stage is referred to, not surprisingly, as the two-word stage and seems to reflect that the child not only understands individual word meanings but also how they can be used to communicate. In other words, toddlers are trying to tell someone something about their world. However, since many of the sounds that adults use, like the “th” sounds and “l” and “r,” are too hard for younger children to say (or even mentally have the concept of at early stages), their speech is often hard to understand for anyone but caregivers who have learned their kid’s patterns of substitutions. 

At this two-word stage, children are still using very rudimentary speech, meant to just communicate what they need and want, rather than constructing the kind of rule-governed sentences they will use as adults. They are still missing the complexities of language like prepositions, adverbial modification, auxiliary verbs, articles, and morphological endings (e.g., adding an -s for plurals or an -ed for the past tense of verbs). At this very early stage, they don’t seem to yet grasp the idea of how adults construct sentences. 

Rather, these early phrases are more along the lines of stringing words one after the other, without any internal modification (such as “a blue ball”) or overarching organization (such as “I want the ball”—the full subject-verb-object pattern most common to sentences in English). But, even at such an early stage, children tend to follow the word order of their language. In other words, they generally prefer to say things like “mama here” (with the actor, mama, coming first and the location, here, coming second) or “mama go” (with the actor first and the verb second) just like adults do.

However, as they move closer to age 3, they start combining words and phrases of much greater length and complexity, with phrases embedding in other phrases like “I no like mama yell doggie”—a vital clue that suggests kids at that age have figured out the rules for merging words into adult-like sentence structures. 

Soon after young children begin to use longer sentences like this, other adult forms such as fully constructed yes/no-questions and passive voice sentences follow, and by age 6 children pretty much have the system down, well before they learn about social preferences like not ending sentences with prepositions or using “whom” instead of “who.” These, instead, are the Those are the kind of standard grammar rules that kids typically learn in school. 

Giving children a linguistic leg-up

So, what does research suggest most helps kids on their path to becoming linguistic experts? Interestingly, there is not much evidence that correcting children’s early mistakes does much to help them master the forms later in life. In fact, kids do not seem to be able to imitate forms that they don’t have a mental conception of yet. For instance, if they have not yet connected the fact that “went” is the past tense form for the verb “go” in English, they are not able to understand when parents correct their use of “go-ed.” 

Nor is there evidence that using simplified language like baby talk or motherese is harmful. In fact, most evidence suggests that the slower, exaggerated speech style might help young children connect sounds, forms, and meanings and improve infants’ language skills (Ramírez et al. 2020). Recent research also finds that caregivers are remarkably attuned to their infants and provide interactive clues such as using more descriptive adjectives (“the big blue ball” vs. just “the ball”), using simpler sentences, and shifting what they’re looking at (for example, looking at the ball when they’re talking about the ball) to help their children learn (Leung et al 2021, Piazza et al. 2020, Roy 2009). Overall, the evidence from psychology and linguistics studies on how children learn language suggests that interacting with children in ways that involve talking (like when you ask questions, talk about things that catch your baby’s attention, or interactively read with your child) is one of the best things you can do to help your child learn the language. Luckily, this is a pretty easy order to fill for most new parents and is surely a lot easier than trying to explain the concept of a preposition or an adverb to a two-year-old.

References

Leung, A., Tunkel, A., & Yurovsky, D. (2021). Parents Fine-Tune Their Speech to Children’s Vocabulary Knowledge. Psychological Science, 32(7), 975–984.

O’Grady, W., J. Archibald, M. Aronoff and J. Rees-Miller. 2017． Contemporary Linguistics: An Introduction (7^th ed.). Boston: Bedford/St. Martins.

Piazza, E. A., Hasenfratz, L., Hasson, U., & Lew-Williams, C. (2020). Infant and Adult Brains Are Coupled to the Dynamics of Natural Communication. Psychological Science, 31(1), 6–17.

Ramírez, Naja Ferjan, Sarah Roseberry Lytle, and Patricia K. Kuhl. 2020． Parent coaching increases conversational turns and advances infant language development. Proceedings of the National Academy of Sciences  117 (7) 3484-3491

Roy, D.K. (2009). New horizons in the study of child language acquisition. Proceedings from INTERSPEECH.