A language is considered to have the word class articles if such a class is clearly differentiated from adnominal demonstrative pronouns (or any other nominal class).[1] Inflection (or declension) of articles is considered to exist if their case function is marked by morphologically distinct variants. To classify the typological status of article inflection, articles should be considered in the form in which they appear alongside predicate verbs.[2] Morphonophological alternation alone does not mark case.[3] Similarly, the phenomenon of an affix or clitic attaching to an inflected noun also does not constitute article inflection. If multiple strategies exist to mark case in the given language, the primary (structurally dominant) strategy should be considered.

Types:

NoCase: The language does not have case inflection.

NoArt: The language does not have articles.

Art=Aff: Articles are affixes and cannot be inflected.[4]

Art=Clit: Articles are clitics and cannot be inflected.[5]

NoArtCase: Articles are standalone words and cannot be marked for case.[6]

ArtAff: Case is marked on articles using suffixes.

AffArt: Case is marked on articles using prefixes.

ArtCaseTon: Case is marked on articles using tone.

ArtCaseInflex: Case is marked on articles using phonemic differences in the stem (internal flexion).

CaseMix: Case is marked on articles using various strategies, with no dominant strategy.

[1] Languages that differentiate the two classes are characterized by the following types of usage: (1) either the article or the demonstrative appears alongside the noun, but simultaneous use of the two in this position is not possible, or (2) both the article and the demonstrative appear alongside the noun. In languages that do not display a clear distinction between the two classes, both the article and demonstrative functions may be represented by a single word, without the possibility of reduplication, thus preventing usage of the aforementioned types. Words that can appear independently in place of a noun are considered demonstrative pronouns.

[2] In terms of this parameter, it is irrelevant whether case forms mark the arguments of the verb or other adverbial functions.

[3] If, for example, case is marked through the use of affixes, it is irrelevant whether the affix attaches to the base form of the article or a variant. Morphological variation of the article is only relevant when it functions to mark case.

[4] This value applies if the noun is marked in the same case even without the article affix.

[5] This value applies if the noun is marked in the same case even without the article clitic.

[6] The noun an article modifies, however, may be marked for case. This should be detailed in the commentary.