Inflection

In grammar, inflection or inflexion – sometimes called accidence – is the modification of a word to express different grammatical categories such as tense, case, voice, aspect, person, number, gender, and mood. The inflection of verbs is also called conjugation, and one can refer to the inflection of nouns, adjectives, adverbs, pronouns, determiners, participles, prepositions, postpositions, numerals, articles etc, as declension.

An inflection expresses one or more grammatical categories with a prefix, suffix or infix, or another internal modification such as a vowel change. For example, the Latin verb ducam, meaning "I will lead", includes the suffix -am, expressing person (first), number (singular), and tense (future). The use of this suffix is an inflection. In contrast, in the English clause "I will lead", the word lead is not inflected for any of person, number, or tense; it is simply the bare form of a verb.

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