Morphological leveling

In linguistics, morphological leveling or paradigm leveling is the generalization of an inflection across a paradigm or between words. For example, the extension by analogy of the (more frequent) third-person singular form is to other persons, such as I is and they is, observed in some dialects of English such as African American Vernacular English, is an example of leveling, as is the reanalysis of English strong verbs as weak verbs, such as bode becoming bided, swoll becoming swelled, and awoke becoming awakened. The original strong forms of these and most other leveled verbs are readily understood by modern English speakers, but are seldom used. Another example is how for all but a few nouns the original English plural suffixes stemming from the Old English weak declension have been replaced by one general plural marker; as late as the 16th century, shoon was still in use as the plural form of shoe, but in contemporary English the only acceptable form is shoes, using the general plural marker -s.

When a language becomes less synthetic, this is often a matter of morphological leveling. An example of this is the conjugation of English verbs, which has become almost unchanging today (see also null morpheme), thus contrasting sharply for example with Latin, where one verb has dozens of forms, each one expressing a different aspect.

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