Mastering any new language is a challenge, but some take much more time and effort to reach proficiency.

The ability to learn a certain foreign language depends on several factors. These include how similar the foreign language is to an individual’s native language (or any other foreign language they might speak), how immersed a person is into the language (studying from books at home versus conversing with the locals), and cultural differences, as well as the complexity of the language itself, in terms of grammar, writing system, and linguistic concepts.

For English-speaking students, the hardest foreign languages to learn include Arabic, Cantonese, Mandarin, Japanese, and Korean. For instance, Arabic has complex grammar and a different alphabet than the Roman alphabet used in English and many other languages. Arabic also has several dialects, which can vary significantly from one region to another, making it difficult for learners to understand speakers from different parts of the Arab world. On the other hand, some of the easiest foreign languages to become proficient in include Spanish and Portuguese.

What’s the hardest foreign language to learn for an English speaker?

There is no official consensus as to what foreign language is widely regarded as the most difficult for an English speaker to learn. However, there is some research undertaken by the United States Foreign Service Institute and the Defense Language Institute that ranked foreign language acquisition by the number of hours students have required, on average, to become proficient in them.

After 70 years of experience teaching languages to American diplomats, the U.S. Foreign Service has grouped foreign languages into four categories of difficulty. The easiest language group requires 575-600 hours of study (23-24 weeks of classroom study) for students to achieve sufficient competence to be posted overseas, whereas the hardest group requires at least 2,200 hours of study (88 weeks of full-time classroom study) to achieve the same level of proficiency. In other words, some languages can be 3-4 times harder to master than others.

Category I Languages: 24-30 weeks (600-750 class hours)

Category II Languages: Approximately 36 weeks (900 class hours)

Category III Languages: Approximately 44 weeks (1100 class hours)

Category IV Languages: 88 weeks (2200 class hours)

Why some languages are harder to learn than others

Although the degree to which an individual manages to master a foreign language can depend a lot on their motivation, almost everything else comes down to how similar your native language is to the one you’re trying to learn.

According to Dr. Cindy Blanco, Senior Learning Scientist at Duolingo, “What makes a language easy or hard is all about what languages you already know — so your native language is really important, but so are any other languages you know or have studied.”

“Adults studying a new language have to suppress the language(s) they know best in order to learn the new system: they have already learned first language conceptual categories for vocabulary and grammar, intricate articulatory motions to pronounce sounds with precise acoustic targets (or manual targets, in signed languages), and maddeningly arbitrary connections between written squiggles and sounds, syllables, or words,” Blanco told ZME Science.

One obvious way that a language can be radically different from another is in the writing system. French uses the same writing system as English, apart from a few extra symbols, so it is much easier to learn than Japanese or Hindi, which have completely different writing systems. Japanese uses three different writing systems, the imported Chinese characters (Kanji), as well as two syllabaries — Hiragana and Katakana. Each writing system has its time and place so you must learn all three.

A vocabulary and syntax that is similar to that of your native language can also make it easier to pick up a new language. If you’re an English speaker you’re quite fortunate, since other languages tend to borrow words from it due to it being spoken across the world.

“We’re apt to transfer properties of our first language to the new language, and that could be helpful if the properties are the same across the languages and more challenging if they differ. Properties include things like first language sounds, concepts and meanings (what counts as “blue” isn’t universal!), patterns for what order to put words in, and rules about politeness,” Blanco said.

However, a common vocabulary isn’t always helpful. It can sometimes work against you. For instance, a French “préservatif” is not something you add to your food, but a condom.

Languages can also differ substantially through the use of different tones. There are four tones in Mandarin: high pitch (say G in a musical scale), rising pitch (like from C to G), falling (from G to C), and falling low then rising (C to B to G). So the same word can have totally different meanings based on its pronunciation. There’s a famous poem in Mandarin by Chinese-American linguist Yuen Ren Chao called The Lion-Eating Poet in the Stone Den, which translated into English sounds like:

In a stone den was a poet called Shi Shi, who was a lion addict, and had resolved to eat ten lions.
He often went to the market to look for lions.
At ten o’clock, ten lions had just arrived at the market.
At that time, Shi had just arrived at the market.
He saw those ten lions, and using his trusty arrows, caused the ten lions to die.
He brought the corpses of the ten lions to the stone den.
The stone den was damp. He asked his servants to wipe it.
After the stone den was wiped, he tried to eat those ten lions.
When he ate, he realized that these ten lions were in fact ten stone lion corpses.
Try to explain this matter.

In Mandarin, the same poem is made of the syllable “shi” repeated 107 times in various intonations.

« Shī Shì shí shī shǐ »

Shíshì shīshì Shī Shì, shì shī, shì shí shí shī.
Shì shíshí shì shì shì shī.
Shí shí, shì shí shī shì shì.
Shì shí, shì Shī Shì shì shì.
Shì shì shì shí shī, shì shǐ shì, shǐ shì shí shī shìshì.
Shì shí shì shí shī shī, shì shíshì.
Shíshì shī, Shì shǐ shì shì shíshì.
Shíshì shì, Shì shǐ shì shí shì shí shī.
Shí shí, shǐ shí shì shí shī shī, shí shí shí shī shī.
Shì shì shì shì.

And that’s nothing — Cantonese actually has nine tones. It’s safe to say, if you’re tone-deaf, you shouldn’t try to learn this language. I’m joking of course, but this extreme example illustrates how tonal differences can contribute massively to making a language extremely hard to acquire.

A foreign language may be based on concepts that are entirely absent in your native tongue, and that may make it more challenging to acquire proficiency. For instance, unlike English, Romance languages such as Spanish and French have gendered nouns, articles, and adjectives. Similarly, in Arabic, you have to conjugate the verb differently depending on the gender of the person, whereas in English it is the same for both genders and very straightforward.

That being said, all foreign languages will present their own unique challenges. But it does get a lot easier the more new languages you acquire.

“For an English speaker, the sounds of Japanese will be (relatively) familiar, and Japanese doesn’t have tones like Chinese or Vietnamese. But the three Japanese writing systems are hard to learn, as are its politeness categories and word order (both really different from English). On the other hand, Chinese has a really challenging sound system for English speakers, but Chinese doesn’t have verb tenses–and that might sound like a relief to any English speaker who has studied Spanish!,” Blanco said.

“Language transfer gets even more interesting when you learn a third or fourth language: you might actually be more likely to transfer properties of your *second* language rather than your *first*! Depending on when and how you learned your languages, your brain might treat your second language as a sort of template for all other languages. This generally means that once you’ve learned multiple languages, each subsequent language is a bit easier: you’re better prepared for the ways in which languages can vary, after you overcome the difficulty of un-learning your first language,” she added.

The languages mentioned earlier are spoken by a sizable number of people, which makes them of interest. There are over 7,000 languages spoken in the world today, but just 23 of them account for half of the world’s population. Roughly 40% of languages are now endangered, often with less than 1,000 speakers remaining. Perhaps some of them are a lot harder for an English speaker to master than Japanese or Cantonese.

Learning any new foreign language can be daunting, but it’s possible to rise to the challenge. Some languages may take much longer to master than others but ultimately it’s all a matter of how motivated you are.

“Motivation is really important in the learning task, since it takes a long time to build up high proficiency in a language. If you’re highly motivated to learn Norwegian because of family ties or because you want to attend grad school there, it’ll be easier for you to stick with it, compared to an “easy” language that you are less interested in sticking with for many months and years,” Blanco said.

This article originally appeared in 2022 and was updated with new information.