The copula is a linguistic item—either an independent word, affix or a clitic—that serves to link the subject to a nonverbal predicate[1], while expressing no other function[2]. When it appears as an independent word, it is usually identical to the verb be. Word order can be determined only if the copula is morphologically expressed; zero morphemes are therefore excluded from analysis.

Types:

NoCop: The language does not have a copula.

CopPred: The copula precedes the nonverbal predicate.

PredCop: The copula follows the nonverbal predicate.

[1] If no such word appears in the present tense, non-present tenses should be examined. If a copula appears in those tenses, then a copular paradigm with a zero morpheme for present tense can be assumed.

[2] Copular verbs that also express a translative function (‘become’) or its opposite (‘stay’ or ‘remain’ something) do not constitute real copulas from a typological perspective, because they can also appear in non-copular languages.