What Is Inflectional Morphology?

Inflectional morphology is the linguistic study of how words are modified to express grammatical categories such as tense, number, gender, case, and voice. The key aspects of inflectional morphology include English Inflectional Morphemes, Functional Role, Conjugation and Declension, and Cross-Linguistic Variation. Inflection is the process of adding inflectional morphemes that modify a verb's tense, mood, aspect, voice, person, or number or a noun's case, gender, or number, rarely affecting the word's meaning or class. 

Words that are never subject to inflection are said to be invariant. Languages that have some degree of inflection are called synthetic languages. They can be highly inflected (such as Georgian or Kichwa), moderately inflected (such as Russian or Latin), weakly inflected (such as English), and very nearly uninflected (such as most varieties of Chinese). Languages that are so inflected that a sentence can consist of a single highly inflected word (such as many Native American languages) are called polysynthetic languages. Languages in which each inflection conveys only a single grammatical category, such as Finnish, are known as agglutinative languages. On the other hand, languages in which a single inflection can convey multiple grammatical roles (such as both nominative case and plural, as in Latin and German) are called fusional languages.

Many languages that feature verb inflection have both regular verbs and irregular verbs. Other types of irregular inflected form include irregular plural nouns, such as the English plurals.

Irregularities can have four basic causes:

• Euphony: Regular inflection would result in forms that sound aesthetically unpleasing or are difficult to pronounce.
• Principal parts: These are generally considered to have been formed independently of one another, so they must be memorized when learning a new word and its inflections.
• Strong vs. weak inflection: In some cases, two inflection systems exist, conventionally classified as "strong" and "weak". For instance, English and German have weak verbs that form the past tense and past participle by adding an ending.
• Suppletion: The "irregular" form was originally derived from a different root.

Two traditional grammatical terms refer to inflections of specific word classes:

1. Inflecting a noun, pronoun, adjective, adverb, article, or determiner is known as declension.
2. Inflecting a verb is called conjugation. The forms may express tense, mood, voice, aspect, person, or number.

Languages that add inflectional morphemes to words are called inflectional languages or inflected languages. Morphemes may be added in several different ways:

• Affixation, or simply adding morphemes onto the word without changing the root.
• Reduplication, which refers to repetition of all or part of a word to change its meaning.
• Alternation, or exchanging one sound for another in the root (usually vowel sounds, as in the ablaut process found in Germanic strong verbs and the umlaut often found in nouns, among others).
• Suprasegmental variations, such as of stress, pitch or tone, where no sounds are added or changed but the intonation and relative strength of each sound is altered regularly.

Hence, inflectional morphology has always been an important base in the world of linguistics. Though its technicalities are lesser known, it still remains a rather essential and salient part of the linguistic studies.