Grammatical conjugation

In linguistics, conjugation is the process of creating derived forms of a verb. This is achieved through inflection, which means altering a word's form according to specific grammatical rules. For example, the English verb "break" can be conjugated into forms like "breaks" or "broke." This process is unique to verbs; when nouns or adjectives change form, the process is called declension. Conjugation generally focuses on creating finite forms, which are verbs that have a specific person, number, or tense. These are distinct from non-finite forms, such as the infinitive, gerund, or participle.

To understand how conjugation works, one must look at the components of a verb. The different forms of a single verb constitute what linguists call a lexeme. The specific version of a verb used in a dictionary is known as the lemma. Most conjugation begins with a root or a stem, which is a modification of that root. When a verb follows standard patterns, it is a regular verb. If it deviates from these patterns, it is classified as an irregular verb. The complete system of all these different forms is called a verb paradigm, often organized into a conjugation table.

Verbs change their shape to communicate many different categories of information. These categories include grammatical person, number, gender, tense, aspect, mood, and voice. They can also indicate possession, definiteness, politeness, or even the speaker's level of certainty, known as evidentiality. Some languages use conjugation to show clusivity, which distinguishes between "we" including the listener and "we" excluding the listener. Other complex factors include transitivity, valency, and reciprocity. The more categories a language tracks through its verbs, the more complex its conjugation system becomes.

Languages vary significantly in their level of complexity. English is considered to have a relatively simple conjugation system. In contrast, languages like French, Arabic, and Spanish are more complex, with single verbs having dozens of forms. Some languages reach extreme levels of intricacy. Georgian, Basque, and Navajo can have hundreds of possible conjugations for every single verb. Agglutinative and polysynthetic languages often have the most complex systems. However, some fusional languages, such as Archi, are also capable of extreme complexity.

A major part of conjugation is verbal agreement, or concord. This is a morpho-syntactic construct where the verb form reflects the properties of the subject or object. In English, we see subject agreement when we say "I go" but must use "he goes." Some English verbs, like "may," show no special subject agreement. In languages with rich agreement morphology, such as Ubykh, verbs can agree with the subject, direct object, indirect object, benefaction, and ablative objects. This high level of detail can allow for a very free word order. For instance, in Basque, the canonical order is subject–object–verb, but any permutation is permitted without causing ambiguity.

In some instances, agreement happens even without a verb. This is known as nonverbal person agreement. In languages like Beja, predicative adjectives receive person agreement that is distinct from verbal conjugation. In Turkic and certain Australian Aboriginal languages, adjectives take affixes identical to verbs, but their negation is different. For example, in Turkish, the person agreement affixes for adjectives are considered nonverbal because of how they behave under negation. This can sometimes be viewed as a form of "verbal takeover" by a copular strategy.

Historically, conjugation patterns have shifted over time. English used to possess a much larger verbal paradigm. Some of these historic forms are still seen in the works of Shakespeare, such as "thou dost" or "he doth." In the Indo-European language family, the verb "to be" is famously irregular. Even so, many related languages show striking similarities in their present tense conjugations. By studying these paradigms, linguists can trace the connections between different languages and understand how human thought is structured through grammar.