This page lists expanded language level descriptions from the main Wikipedia:Babel page. The level descriptions are listed below. Note that, as the purpose of the Babel system is to help collaboration in making an encyclopedia, proficiency in the written language should be more relevant than that in the spoken language when choosing levels. The Japanese language is a particular case, due to its writing system: if you know enough kanji to read simple texts, but probably not encyclopedia articles, you should classify yourself as low as ja-2, even if you can write Japanese more fluently than that using kana.

xx-0
You might be expected to understand a language (e.g. if you often contribute to articles about it, or you live in an xx-speaking country), but don't actually understand it at all, or not well enough to qualify for xx-1. You do not need to use xx-0 for every language you do not know.
xx-1
You can understand a language well enough to use an article as a source for writings in your own language, and to ask and answer simple questions in it, e.g. on a user talk page (possibly with the aid of a bilingual dictionary), but are unable to contribute significantly to an article in that language.
xx-2
You can contribute to articles in a language to some extent, but are not confident in writing in it. Someone using this template will most likely not be fluent in a language but will understand the general idea as well as many details in an article (although a poorly educated native speaker may use this template). This template might be used by editors who have a sizable vocabulary as well as good understanding of the grammar of the language in question, but who might have trouble creating new articles or writing in an encyclopedic style. You would most likely be able to coherently translate most articles using a dictionary. [clarification needed]
xx-3
You are confident in writing in a language in an encyclopedic style, but may make minor mistakes, and have trouble with some of the most peculiar features of the language. You should probably only need a monolingual dictionary to understand any non-technical article.
xx-4
You are as proficient in writing and understanding articles in an encyclopedic style as an average educated native speaker of xx. Since users of this template are usually not native speakers themselves (because of its wording, and because the xx template corresponds to the same level of proficiency), they might be unfamiliar with some colloquialisms, some aspects of popular culture of xx-speaking countries, etc.
xx-N
For native speakers. You should use this template if you have lived in an xx-speaking community or employed it in all everyday situations long enough that now you have a perfect grasp of it, including colloquialisms and idioms. It should be noted the "lived in" part is not that important; it's the "including colloquialisms and idioms" part that matters primarily.
This means that if you moved from an xx-speaking country to a yy-speaking country at age 6, and have never again spoken xx, you should classify yourself as a native speaker of yy and not of xx, even if you used to speak nothing but xx as a child.
Should you have moved as an adult, you can decide by yourself, according to your own "feel", and thus might have several "native" languages.
Used alone, this template indicates that your proficiency in writing and reading encyclopedic language is that of an xx-4 user; if it is not, you might want to use both xx and one of the xx-n templates; for example, if you are a native speaker of xx but you were not educated in it, you could use both xx and xx-2.
xx-5
You work in a field in which proficiency in the formal written language is essential, for example as a writer, a copy-editor, a language teacher, …; you are willing to give advice about language issues such as grammar, punctuation, etc. if requested (for the language of the project on which the template is used, English in this case), or to help in translations from this language (for other languages). If you also are an xx native speaker, you may wish to use both xx and xx-5.

See also

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