At some point in early childhood you started to connect the sounds and shapes of words with their meanings. Using words to initially express basic needs and wants — warm food or your favorite blanket — you eventually moved to advanced stages of relaying thoughts and feelings, slowly but surely developing a foundation of language. Odds are you rarely thought about the science of language until you actually studied English or attempted to learn a second language.

There is a complex interplay between physical and social language. Indeed, as any linguist can attest, learning a language considers elements of neurology, physical health, mental aptitude, socioeconomics, parenting and education. The way we learn language determines how effectively we give a speech before a large audience or a pep talk to a loved one. Understanding how we learn language is as fascinating as the learning of language itself.

“Language is always changing,” said Andrew Stafford, an assistant professor of modern language studies and French at Lycoming College in Williamsport, Pennsylvania. “And now with technology providing instruction, language is really changing. Language, though, is a skill. Like walking or riding a bike, even if you learn a language and stop using it, it’s not that you lost it but how you revisit its changes.”

Starting It All With Baby Talk

The reason why linguists and scientists believe that learning a native language comes easy is because we’re not overtly trying to learn it. It’s a natural process, rather than a studied one. This organic “class” starts early: in the womb. Researchers found that the melodies in the cries of 30 French and 30 German newborns matched the sounds of their native languages. The only way they could perform such a natural symphony was by hearing their mothers’ words before birth.

From there, language learning seems to start with baby talk.

A study of 2,329 babies in 16 countries showed that most of them responded best to infant-directed speech, as opposed to their caregivers speaking to them more like adults. “Often parents are discouraged from using baby talk by well-meaning friends or even health professionals. But the evidence suggests that it’s actually a great way to engage with your baby because babies just like it. It tells them, ‘This speech is meant for you,'” Michael Frank, a Stanford University psychologist and member of the organization that conducted the study, ManyBabies Consortium, told Stanford News.

From infancy on, language learning continues at a brisk pace. Children can say around 10 words by 13 months, 50 by 17 months and 300 by the age of two, as reported by Science Focus. By the time children are six, they can say about 3,000 words and understand a third as much.

Yet, children learn not just words and their meanings, but also how to properly construct sentences and understand many complex operations of grammar: multiple definitions of words; past, present and future tenses; noun-verb agreement; arrangement of subject and object; verb conjugation and so much more.

Those studying the science of language still can’t say with certainty how people naturally learn that complicated dance. Certainly, observation and practice make almost perfect but there’s more to it than that. As Science Focus notes, it’s believed that no child receives enough input from external sources to speak and write with the depth and understanding that they do. But it’s also obvious to many experts that a native language isn’t learned simply through rote exercise. It probably boils down to children observing how adults speak and applying this new language to relatable situations, even if they break the rules along the way.

Age Matters When Learning a Language

Breaking the rules is just fine, according to Stafford of Lycoming College. When teaching French to students who already know one language or several, Stafford asks them to not focus as much on grammar or punctuation but to use the words to “accomplish something.”

He added: “The teaching has shifted from an understanding of the inner workings of language, to more of an understanding of the output and how it’s used. That has translated to a more hands-on approach to learning. In the end, language is used for communication. Whether it’s perfect pronunciation or grammar, if you get your meaning across, you’ve accomplished your goal.”

Stafford’s students are mostly older than 18. That means they’ve just creeped past what is believed to be a peak age for language learning, 17 or 18, as an MIT study posits. The study also found that unless people start learning a language by the age of 10, it’s nearly impossible to achieve proficiency similar to that of a native speaker. However, those between 10 and 18 still learn faster than an adult will.

What stumps the MIT experts and other researchers is why the critical learning period is during youth and not later in life. The MIT researchers suggest that cultural factors play a role, as well changes in brain plasticity that occur around 18.

Bilinguals’ Brains Show a Process

Linguists and scientists are also fascinated by how people learn non-native languages. For instance, a University of Delaware study of 24 native English speakers attempting to understand Mandarin Chinese focused on the roles of the brain’s left and right hemispheres in language acquisition.

The study, which included brain scans of the students, found that the left hemisphere of the brain, which is identified as the language learning side, took a back seat to the right hemisphere. The process of distinguishing acoustic details of sounds, the researchers say, happens on the right side of the brain, a finding that could help with the learning of foreign languages.

No matter the learner’s age or level of fluency in understanding two or more languages, experts love to look at the brain to determine our way with words.

Ping Li, a professor of psychology and linguistics at Pennsylvania State University told Psychology Today that learning the many facets of a language means using the many parts of the brain. Despite the claim by commercial products, he said, people cannot learn a language in a day. The brain needs time to work through it all.

Li explains: “The lexicon engages the frontal and parietal cortical regions, phonology uses your frontal and temporal regions, orthography uses your occipital and temporal-parietal regions, syntax engages your frontal and subcortical regions, and pragmatics relies on both the left and the right hemispheres.”

Take a Train or Start a War?

Even though Li contends that programs promising quick mastery of a language shouldn’t be believed, technology might help. For Stafford, it all depends on how you want to learn a language.

After downloading a language learning app, Stafford noted that it aimed to put a language’s words in order to express certain meanings, but it lacked one noticeable learning mechanism: interaction with people who speak the language. “It doesn’t show how people react to it,” he said. “So, am I really learning it? No.”

To test how well language programs teach based on potential interactions, he downloaded another application that allowed him to speak into his phone, with the promise that the program would analyze his pronunciation and offer corrections.

The word for a train station in French is “gare.” The French word for war is “guerre.” Stafford says they sound similar. He said “guerre” to the application, and it informed him he was 75% accurate in pronunciation. For people learning French, that’s not enough, he said. “What if I asked someone to help me find the “gare” but I didn’t pronounce it correctly and the person said to me, ‘Why are you talking to me about the war?'”

No matter how natural or hard it is to learn a language, how you learn it matters, according to Stafford.

“A big point of linguistics is, what is the motivation of learning the language?” he said. “That’s way more important than anything else.”