The answer to the question what is the hardest languages to learn depends on one’s own native language. Languages are not equal: some are more structurally, phonetically, and syntactically complex than others. For instance, for me a Moroccan Canadian whose native language is Arabic, learning the different Arabic dialects spoken in the Middle East is pretty easy. Most of these dialects descend from classical Arabic, which is the proto-language or the parental language.

For an English native speaker, Arabic is one of the hardest languages to learn. Why? Because Arabic, among other reasons, descends from a different language family (i.e, Afro-Asiatic) than English (i.e, Indo-European) which explains why Arabic script, letters, grammar, syntax, and intonation are all different. 

For a native English speaker, to learn Arabic is to embark on a completely new language learning experience, which is not the case when they are learning another language within the same language family, that is, an Indo-European language such as French, Spanish, or any other language which shares a common ancestral language.

If you ask a multilingual person (i.e., a person who speaks two or more languages) about their foreign language learning experiences they will certainly tell you that they found a certain language hard to learn compared to other languages they learned. 

For instance, in my case, besides Arabic as my native tongue, I also speak French (second language), English, and a little bit of a communicative German. Which of these languages was hardest to learn? French. Its syntactic and conjugation systems are way more complex. 

For instance, unlike English, French has gendered definite articles: Le and La.  ‘Le’ is used to pre-modify a male noun and ‘La’ a female noun. This rule alone requires so much time and energy to learn and even established French speakers still make mistakes in the usage of Le and La.

However, to attribute language difficulty solely to the differences in ancestral language decent is to miss the point and fail to understand the immeasurable complexity of human language. 

There are various other factors that make certain languages hard to learn and you can turn to historical linguistics for nuanced answers. But suffice it to say here that certain languages, as stated in the language learning literature, are especially hard to learn for English speakers.

As I was working on  Best Languages to Learn, I had the chance to consult several reliable online resources that feature the hardest or most difficult languages for English speakers to learn. All of these lists unanimously feature Arabic and Mandarin among the hardest languages to learn.
According to Lifehack, the 7 hardest languages for English speakers to learn are :


As for Babbel, these are the 6 hardest languages for English speakers to learn:

Mandarin ChineseArabicPolishRussianTurkishDanish

For Rosetta Stone, their list of the hardest languages for English speakers to learn comprises the following languages:

Mandarin ChineseArabicVietnameseFinnishJapaneseKorean

For Busuu, these are are the 8 hardest languages for English speakers to learn:

HindiHungarianNavajoVietnameseKoreanArabicJapaneseMandarin Chinese

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