You’ve probably heard that it’s extremely difficult for adults to learn a second language. You may even have proof: You tried it yourself, and it didn’t work. But maybe that’s because you took the wrong approach.

Stephen Krashen has a better idea. In the 1980s, Krashen, now professor emeritus at the University of Southern California, developed the Comprehensible Input Theory of language acquisition. The word acquisition, as opposed to learning, is key.

Learning is what you did in school: memorizing vocabulary lists and rules of grammar, taking tests, and awkwardly trying to pronounce Me llamo Juan or Comment vas-tu? Acquisition, on the other hand, is picking up a second language in more or less the same way you learned your first: by listening to and engaging with people speaking the language. Your brain does the rest without much conscious effort on your part. 

In a sense, comprehensible input, or CI as its adherents call it, is like being thrown into the deep end of the pool and figuring out how to swim. But with language learning, that’s neither as traumatic nor as cruel as it sounds. That’s because your brain can learn language just by being surrounded by it. The brain is a pattern recognition machine, so sorting out the patterns of a language is part of its skill set. In fact, that’s how you learned your first language.

How Do Babies Learn Language?

Babies learn their native tongues effortlessly, or so it seems. How do they do it? Certainly not by poring over vocabulary lists and filling out grammar worksheets. Parents don’t sit their children down with a set of flash cards. Instead, they talk to them. And, eventually, the children start talking, too.

It seems like magic, but it’s not. Children are born with the ability to process the statistical patterns in language, making them ripe for learning language, according to Roberta Michnick Golinkoff, a cognitive scientist and expert in language learning at the University of Delaware.

But even if it’s mostly unconscious for both the child and the parents, there’s some method involved. Golinkoff points out that when adults speak to babies, they speak in a special way.

“You’re not going to have a conversation with your kid about death and taxes,” she says. “Parents tend to talk to kids in a way that offers them what they need. They say something like, ‘Oh, look at this little shoe. You have a red shoe.’ You talk to children mostly about the here and now.”

In “From Coo to Code: A Brief Story of Language Development,” a chapter in The Oxford Handbook of Developmental Psychology, Golinkoff and her coauthors explain that parents also use something called infant-directed speech when talking to babies. They speak more slowly and use shorter phrases, simpler words, and exaggerated intonation. You and I call this “baby talk,” and research has shown that babies love it, and it helps them learn language.

Read More: Native Language May Wire the Brain in Unique Ways

How to Learn a Language with Comprehensible Input

Obviously, you’re not a baby anymore, and you don’t have someone doting over you, speaking baby talk in the language you want to learn. But the CI method offers something similar.

There are many variations, but the process of using CI to learn a second language goes something like this: You find content in the language you want to learn, and you listen to (or, in some cases, read) that material regularly. It’s important that the material be understandable (that’s where the comprehensible part comes in). You won’t make much progress if you just tune in to a foreign language TV station and let the unfamiliar language wash over you.

But if you start with the adult equivalent of baby talk — simple language backed up with gestures, pointing, and pictures — you’ll gradually make progress. As you process more and more input, you’ll be able to comprehend more complex material. You gradually increase the complexity until, like a child, you find that you can understand and even speak your new language with relative ease. 

Ideally, you’ll find content that you can understand but also enjoy. The very best content is material that’s so interesting that you forget you’re listening to a foreign language. These days, that’s easier than ever to find. Websites and podcasts provide a wealth of material at all levels, from YouTube videos to apps and online courses. And social media makes it easy to find talk partners — people who will talk with you in your target language.

Read More: How Language Shapes Our Understanding of Reality

Why Learning a Language as an Adult Is Challenging

John Grundy is a neuroscientist who studies brain plasticity and bilingualism at Iowa State University. He explains that one of the biggest differences between learning a language as a child and learning a new language as an adult is that children are consistently immersed in the language environment, talking back and forth with their parents and maybe with siblings.

But adults, often pressed for time, typically learn in a classroom a few times a week or maybe on their own through books and videos. If adults were to have as much immersion as kids, they’d learn more and learn faster, Grundy says. CI can’t provide that level of immersion, but it’s much closer than the typical classroom experience.

Just like babies don’t learn by magic, CI is not a magic wand for learning language. You have to put in the time. One popular program for learning Spanish using CI estimates that it takes 600 hours of input to reach the advanced level (and that’s still not the level of a native speaker). That’s a long time, but you didn’t learn your native language overnight. If the material is interesting enough, adherents say, CI can be a fun and effective way to learn a second language.

Read More: How Learning a Language Changes Your Brain

Article Sources

Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:

Avery Hurt is a freelance science journalist. In addition to writing for Discover, she writes regularly for a variety of outlets, both print and online, including National Geographic, Science News Explores, Medscape, and WebMD. She’s the author of “Bullet With Your Name on It: What You Will Probably Die From and What You Can Do About It,” Clerisy Press 2007, as well as several books for young readers. Avery got her start in journalism while attending university, writing for the school newspaper and editing the student non-fiction magazine. Though she writes about all areas of science, she is particularly interested in neuroscience, the science of consciousness, and AI–interests she developed while earning a degree in philosophy.