Konjugatsioon

Konjugatsioon is the systematic inflection of verbs to express grammatical categories such as person, number, tense, mood, voice, and negation. It encompasses how a verb changes form across different contexts, enabling subject agreement and precise expression of time and aspect. Conjugation patterns vary widely between languages: some have a few regular endings, while others feature many irregular forms, stem changes, and suppletive forms. In linguistics, conjugation is distinguished from other verb-related processes by its focus on inflected verb forms rather than base lemmas alone.

Across languages, verbs typically form their different shapes through affixation (suffixes, prefixes, or infixes), internal vowel or consonant alternations, or combinations of these methods. Some languages rely heavily on periphrastic constructions—using auxiliary verbs together with participles—to express tenses or aspects. In others, a single verb may have dozens of distinct forms within a single tense or mood. Conjugation systems often organize verbs into classes or patterns, called conjugation classes, that share the same set of endings.

In Estonian, for example, verb forms reflect person and number in the present tense: ma näen (I see), sa näed (you see), ta näeb (he/she sees), me näeme, te näete, nad näevad. The past tense appears as ma nägin, and the perfect tense uses an auxiliary plus a past participle, as in olen näinud (I have seen). Negation commonly uses ei: ma ei näe (I do not see). Irregular verbs and stem changes add further complexity to the system.

See also: morphological inflection, verb conjugation in different languages, irregular verbs.