5 Pronunciation Patterns from Around the World

June 10, 2025

Dear Duolingo: What makes a word’s pronunciation change?

Your tongue is always looking for shortcuts!

Welcome to another week of Dear Duolingo, an advice column just for learners. Catch up on past installments here .

Hello, learners! Dr. Emilie Zuniga here. As a hyperpolyglot linguist, I love everything about languages, but my favorite topic is pronunciation. I even wrote my dissertation about special vowel sounds in a dialect of Arabic in southern Turkey. 🤓 But there are actually pronunciation patterns that apply to all languages, and that’s what this week’s question is about.

Our question this week:

Well, Sounds Silly, you’re right—we could just keep pronouncing things the same way! But what’s fascinating about language is that we don’t. 🤷🏻‍♀️ Typically, we don’t even realize that a word’s pronunciation is changing, so the changes start really small until after a long time, it might be hardly recognizable.

There are many reasons why pronunciation changes over time (and also good reason why it sometimes doesn’t), and since languages are always evolving, sounds do, too. Some change is motivated by factors like our identity and bilingualism, and other pronunciation changes actually come right from our mouths!

Our mouths (or hands, for signed languages) have to strike a balance between competing demands:

There are so many meanings and nuances we want to convey when we communicate.
We have to convey all those meanings quickly, packing tons of information in just seconds (or split seconds!).
Each language has a relatively small set of sounds to work with—and even if a language used all the sounds possible for humans to make, it would still be only a couple hundred!

There is a push-and-pull always happening when we pronounce words: We need things to be as clear as possible (for all those different meanings!)… but also as efficient as possible (to make good use of our language’s sounds and to say all those words quickly).

5 common sound changes—worldwide

As a result, there are certain sound changes that are especially common across languages and throughout time, to balance clarity and efficiency. Let’s take a look at five of the most common!

1. Sounds become more alike

Formal name: assimilation
What it is: one sound becomes more like a neighboring sound
Why it happens: to make pronunciation easier or faster by reducing how many different pronunciations your tongue has to make
Example: Latin i n possibis → i m possibilis (impossible)

The final “n” in the Latin prefix “in-” (meaning “not,” “non-”) changed to “m” before “p” and “b.”
All three of those sounds (“m,” “p,” “b") are made with the lips coming together, unlike “n” (which is made behind the teeth).
Because this sound change happened before Latin evolved into the Romance languages we know today, all those languages use im- as the negative prefix in their version of impossible ( i m possible in French, i m possibile in Italian, etc.).

Example: Old Arabic الزيت a l-zayt → Classical and modern Arabic a z-zayt (the oil)

The Arabic word for “the” is usually اﻟ (al-), but if the following word starts with a sound produced in nearly the same place in your mouth as “l,” that “l” just becomes the same sound.
Fun fact: الّزيت az-zayt (the oil) was borrowed into Spanish altogether as the word for “oil” ( aceite)... and no trace of the original “l.” That also means that when you say el aceite (the oil) in Spanish, you’re saying “the” once in Spanish and once in Arabic!

2. Sounds become more different

Formal name: dissimilation
What it is: one sound becomes less like a nearby sound
Why it happens: to reduce repetition or make sounds easier to distinguish
Example: Classical Latin pe r eg r inus → French pè l e r in (pilgrim)

The first “r” in peregrinus became an “l” to make it distinct from the second “r.”
Most Romance languages also made this change away from the two “r” sounds (Italian pe ll eg r ino, Catalan pe l eg r í, Romanian pe l e r in), but Spanish and Portuguese kept them both ( pe r eg r ino), sticking with the pronunciation that requires your tongue to move back and forth to the same place in your mouth.

Example: Old French l ive l → n ive l → Modern French niveau (level)

The first “l” in Old French livel became an “n” so it would sound different from the second “l.” (The sounds “n” and “l” actually have a lot in common, when you look at how they’re pronounced!)
English got the word level from French before this sound change took place—it’s a pronunciation relic!

3. Sounds become less forceful

Formal name: lenition
What it is: a consonant becomes weaker in some way (there are some technical definitions around what this means, but the basic idea is that a more forceful sound becomes less forceful!)
Why it happens: to make pronouncing a word less effortful
Example: Ancient Greek βιβλίον b i b lion → Modern Greek βιβλίο v i v lio (book)

Ancient Greek “b” became a “v” sound.
The sound “b” entirely blocks the passage of air—you can even see it, when the speaker’s lips come together and pop apart! The sound “v” is different: The teeth only partly block airflow so some air still gets through. That counts as less effort, since you don’t have to block air so tightly.

Example: Proto Semitic *pay- → Modern Standard Arabic فم fam and Moroccan Arabic فم fomm (mouth)

In Proto Semitic, the ancestor of all Semitic languages (which includes Arabic), the root word for “mouth” started with the sound “p,” but that sound has evolved into “f.”
Similar to the Greek example, “p” fully blocks airflow while “f” allows some air to pass.

4. Sounds move towards the roof of the mouth

Formal name: palatalization
What it is: a consonant is produced closer to the roof of the mouth (also called the hard palate)
Why it happens: usually to help the tongue move towards a high vowel just before or after the consonant, to reduce the distance between one sound and the next
Example: Latin de → Brazilian Portuguese de (from, of)

In Brazilian Portuguese, “t” and “d” are commonly pronounced like “ch” and “j” when the next sound is “i.”
As a result, “t” is pronounced like “ch” in ó ti mo (great) but it stays “t” in tô nico (tonic), and “d” becomes “j” in de (from, of) but is pronounced “d” in da do (dice).

Example: Latin dicere → Québécois French dire

In Québécois French, “t” and “d” also change before high vowels, though they sound a little different than their Brazilian Portuguese counterparts.
The sounds are pronounced in the original locations, closer to the teeth, for tête (head) or don (donation, gift). It all depends on the following vowel!

5. Sounds switch places

Formal name: metathesis
What it is: the order of different sounds in a word is switched around
Why it happens: often begins as an accident and over time becomes the standard
Example: Proto-Germanic *aiskōn → Old English a sc ian and a cs ian (to ask)

Around a thousand years ago, the Old English verb for “to ask” had two forms: one like aks and one like ask!
The “k” and “s” sounds swapped places in different dialects, so some dialects (including African American English) ended up with aks as the most common form and others have ask. These sounds have continued to swap places over time.

Example: Old Arabic زوج z aw j → Levantine Arabic dialects جوز j oo z (husband)

The sounds “z” and “j” got switched in many Arabic dialects (not just Levantine!).
Interestingly, there was already a word جوز j oo z, meaning “nut,” but this didn’t prevent metathesis from happening to the word for “husband”!

Your tongue is doing its best!

And those are just a few of the sound changes you can expect. Once you know that they’re not random quirks, they can help you make connections between seemingly different words… which can actually make language learning easier! 🌍🔍

For more answers to your language and pronunciation questions, get in touch with us by emailing dearduolingo@duolingo.com.