Why Is It So Hard to Learn a New Language as an Adult?

Thursday, August 244 min read

About half of the world’s population speaks at least two languages, but that emphasis on learning multiple languages isn’t as prevalent in the United States. According to the U.S. Census Bureau, only 20% of Americans speak a second language. Aside from the time and dedication it takes to learn a second language, other factors including age and the type of language play a big role in our ability to learn this new skill.

Age Makes a Difference

Research supports the idea that there is a critical age period for maximum proficiency in learning a new language — the younger, the better. According to a study by MIT, that age cutoff is 10. A language student who begins studying before the age of 10 has a chance of becoming as proficient as a native speaker would be, but after age 10, it is nearly impossible to become that proficient.

However, those between the ages of 10 and 18 still have a higher retention rate than older learners, especially when it comes to learning new grammar. Researchers aren’t sure why retention rates drop so dramatically after age 18, but it could be due to cultural and social changes at this age (such as moving out of the family home) or biological reasons (changes in brain plasticity).

It’s still possible to learn a new language at any age, but it seems that children do have an advantage.

Advantages of Learning as a Child

Brain chemistry: Children are built to absorb new information, even unconsciously.

Learning style: Children are implicit learners, and better at listening and imitation. It’s what their brains are wired to do at that age.

Material and context: Children are taught small bits of simple information, including colors, numbers, songs, and shapes, whereas adults tend to be taught more complex language ideas.

Confidence: Children aren’t afraid to mess up a word or fumble through a sentence, whereas adult learners are less likely to practice new skills out loud. Practicing out loud is one of the best ways to master a new language.

Advantages of Learning as an Adult

Learning style: Adults are explicit learners who are better at intentionally learning a new language through lessons. They also have longer attention spans and more literacy skills. When tested in formal language labs, adults performed better than children.

Dedication: Children might not have the same motivation or level of dedication as adults do when learning a second language.

Overall, there are advantages for learning a second language at any age. Children might have an easier time becoming proficient, but adults can still have great success in learning a second (or third, or fourth) language.

Type of Language Makes a Difference

Some second languages are easier to learn than others, and the answer of “which language is easiest” varies based on the speaker’s native language. The closer a language is to an already-learned language, the easier it will be to learn. The most difficult languages to learn typically have a different alphabet. For example, French is an easier language for an English speaker to learn because they use the same Latin alphabet, whereas Greek would be more difficult because it uses the Greek alphabet.

Easier New Languages for English Speakers


According to the U.S. Census, Spanish is the most common non-English language spoken in the U.S. It is also one of the easiest for American English speakers to learn because both languages use the Latin alphabet and share many cognates (words that have the same definition and sound very similar), such as “airport” and aeropuerto and “hotel” and hotel.


Norwegian and English are both members of the Germanic language family, so they share a lot of the same vocabulary. These languages also have similar sentence structures. For example, “Can you help me?” is written as Kan du hjelpe meg? — a direct translation.


Many Asian languages are difficult for English speakers to learn, but Indonesian is the exception. It is one of the few Asian languages that use the Latin alphabet, and it’s a phonetic language, meaning that words are pronounced as they’re spelled.

Other easier second languages for native English speakers to learn are Swedish, Dutch, Portuguese, Italian, and French.

Difficult New Languages for English Speakers

Any second language that uses a different alphabet or very different sentence structure will be more difficult to master. Additionally, some languages are tonal (English is not), meaning that the pitch of a word conveys (and changes) its meaning, something English speakers are not used to. This is the case in many Asian languages, including Vietnamese, Chinese, and Thai.

Mandarin Chinese

Mandarin Chinese is one of a few Chinese dialects, but it is the most popular. It is a tonal language composed of four tones, meaning that one word can be pronounced four different ways. Ma means “mother,” “horse,” “rough,” or “scold,” depending on how it is said. Mandarin Chinese also uses thousands of special characters that can be difficult for English speakers to memorize.


Arabic is very different from English in that it excludes most vowels, is written from right to left, and uses its own alphabet. Some Arabic sounds, especially those made in the back of the throat, are difficult for native English speakers to master.


Polish is one of the most difficult European languages for English speakers to learn. Although it uses a Latin alphabet, the Polish alphabet has 32 letters (including diacritics, or letters with accent marks), compared to the 26 letters in English. Polish words tend to be long and packed with consonants and accents. Polish grammar is also more complicated: It has seven cases, whereas Englishhas three (subjective, objective, and possessive).

Other difficult second languages for native English speakers to learn are Russian, Turkish, Danish, Hungarian, Vietnamese, and Thai.

However, when starting from scratch — as a baby would, with zero knowledge of any language — there is no language in the world that is more or less difficult than another.

Featured image credit: fizkes/ iStock

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