Growing up in a country as multilingual and diverse as India gives one the ability to pick up at least two or three languages to be used on a daily basis. But, some people may end up getting the shorter end of the stick — they can sometimes only understand a language without actually being able to speak it — a phenomenon officially called receptive multilingualism.

This is often more commonly described as passive multilingualism — which implies one knows but can’t assert any agency over the language. But that categorization is misleading because the brain works quite hard to channel languages for the purpose of communication.

There are two parts of the brain involved in the process of speaking and understanding language — Wernicke’s area in the temporal lobe (located under the ears), which comprehends language, while Broca’s area in the frontal lobe (located behind the forehead) deals with speaking language. Both regions stretch between the left and right hemispheres of the brain and are connected by axons (neuron stems) known as the arcuate fasciculus, which act as a link to transfer information about languages between both brain areas.

Receptive multilingualism occurs because there is a radical difference in the cognitive efforts required to undertake the brain activity of comprehending a language and speaking it.

If you’ve been exposed to a language for a sufficient period of time, understanding it is easier and faster than communicating in it. This is because understanding a language involves the brain’s ability to infer things from phonemes — distinct units of sound that help us differentiate between words — which the brain then segments into phrases or sentences. The rest is worked out by our ability to infer what the other person means. Think of it this way: assume you grew up listening to your family speak English though you only speak Hindi. Now, if a person says, “The weather is quite hot outside!” — your brain picked up weather, hot, and outside, because you’ve heard them say those words before, which allowed you to infer the person is telling you about the hot weather outside. This ability is boosted if the language you understand is related to the language you speak. For instance, if you speak Malayalam, you’re likely to find understanding Tamil easier, as they are both are rooted in the Indo-Dravidian language family.

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However, speaking language is a whole different ball game, with a significantly higher cognitive load. First, you must come up with how you would like to respond — say. you agree and want to talk about how you miss the monsoon. Your brain has immediately responded internally with ‘kaash barish ka mausam hota.’ Now, you must morph it into the very specific linguistic sentence structures and phrasing unique to the English language — you can’t directly translate it to ‘wish rain of season would’ because that makes no sense as an English phrase. Your brain needs to rewire your Hindi response to ‘I wish it was the rainy season.’ After that, your brain must recall the ways in which the words are pronounced and speak them. This particular set of functions are possible only via repeated practice, almost like we’re training the brain’s muscle.

The cognitive load of understanding several languages and switching between them at high speed while understanding and speaking is serious business: it is intense enough to boost gray matter volume and increase the size of something called the anterior cingulate cortex, which plays a role in controlling what language we speak in a particular context. It comes as no surprise that research uncovered a correlation between bilingual individuals in India and a slower rate of developing dementia — a disease staved off by increased brain exercise and more gray matter volume — than monolingual individuals.

There is also a unique social phenomenon that prevents individuals from speaking languages they understand so well — fear of failure and shame. Individuals often don’t focus on learning to speak certain languages, as maybe the said language is irrelevant to their location and context. For example, second-generation immigrants favor learning the language spoken in the country they live in, rather than their mother tongue. Lack of practice and exposure to a language can also erode an individual’s previously learned ability to speak it fluently, making them self-conscious of conversing in a particular language overall. This is uniquely reflected when certain people are able to speak foreign languages more fluently and confidently while inebriated or under deep hypnosis, when they aren’t as inhibited as they are while sober or conscious.

Receptive bilingualism is a unique linguistic phenomenon that highlights how language takes root and branches out into proper forms of communication. For those who’d like to do more than understand, the best way to move beyond merely understanding a language is to practice speaking it until you develop the confidence to be fluent.

You could say practice speaks for itself — quite literally, in this case.