What is the hardest language to learn? It's one of the most spoken languages in the world.

Some may remember taking foreign language classes during school or in preparation for a new job or some travel.

There are over 7,100 spoken languages in the world, according to Ethnologue. While it’s hard to count an accurate number of bilingual speakers in the United States, there are over 63 million people who speak more than one language.

Whether you want to brush up on a forgotten language or start a path to learn about other cultures and customs, there are many factors involved in learning a new language.

What is the hardest language to learn?

Mandarin Chinese is the number one language listed as the most challenging to learn, according to multiple sources. The Defense Language Institute Foreign Language Center – where members of the military, government employees and law enforcement officials study – puts Mandarin in Category IV, which is the list of the most difficult languages to learn for English speakers. The languages in that list have 64-week-long courses.

One reason Mandarin is seen as the most challenging to learn is because its writing system uses characters that might be difficult to grasp for those accustomed to writing with the Latin alphabet, according to the language learning platform Babbel. While there are over 100,000 characters in Chinese, according to the Chinese Learning Institute, you only need to know around 3,000 to become fluent.

Babbel also says Mandarin is hard to learn because it is a tonal language, in which “a word’s meaning has to be affected by the tone.” An example of this in English that Babbel cites is using a higher pitch at the end of a phrase to indicate it’s a question. Although English and other languages use tones, that does not automatically make them tonal languages.

iChineseLearning lists Mandarin tones using the “ma” example. Depending on the tone, the word can either mean “mom,” “numb,” “horse” or “to curse.”

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How many tones are in Mandarin?

According to FluentU, Mandarin has five tones: the first tone (flat tone), second tone (rising tone), third tone (dip tone), fourth tone (falling tone) and fifth tone (neutral tone).

FluentU includes the neutral tone in its list, where there is no variation in pitch. Whether the neutral tone is even a tone is debated.

What is the most spoken language in the world?

According to the language-education company Berlitz, English is the most spoken language in the world, with 1.13 billion speakers; 379 million people are native English speakers. Mandarin comes in second with 1.12 billion speakers, with 918 million native speakers.

What is the easiest language to learn?

Spanish is the easiest language to learn, according to Busuu and Jumpspeak language-learning programs. They cite these factors:

Busuu's rating:

  • Spelling: Very easy

  • Pronunciation: Very easy

  • Grammar: Fairly easy

Jumpspeak's rating:

  • Speaking: Very easy

  • ‍Grammar: Very easy

  • ‍Writing: Easy

  • ‍Overall: Very easy

Aspects of learning a language

Dr. Cindy Blanco, senior learning scientist at Duolingo, explains on the website different aspects of language learning that gauge how easy the process could be.

The meaning behind you learning a language

If you’re learning a new language to prepare for a vacation, the scope of what “knowing” means to you is smaller than someone who is learning because they have a new full-time job abroad, Blanco says in the article. She says to prioritize staying on track with personal goals instead of being put off by learning a hard language.

Language difficulty is subjective

When learning a new language, we usually transfer what we know from our first language to our second, third and so on, Blanco says. This includes hand gestures, body language, sounds, cultural norms and more.

There are easy and hard aspects of learning any language

Maybe you’re great at speaking Spanish, but when it comes to writing or reading, those aspects are harder for you. For someone used to writing with the Latin alphabet, a language that uses a different writing system could make grasping a new language more difficult, Blanco says. Every part of language learning isn't 100% easy or 100% hard.

Motivation and the opportunities around you

Someone who lives in Seoul might have an easier time learning Korean because of their environment, Blanco says, even though another language might technically be easier to learn.

Motivation is another key part in determining the difficulty of a language. If you are taking on a language because of a new job abroad, it will be easier to continue the process than with another language.

Blanco concludes that studying a language closer to the one you already know is the easier option. For a native English speaker, this might be European languages like Dutch or French, according to Matador Network.

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This article originally appeared on USA TODAY: What is the hardest language to learn? Plus the easiest to pick up.