Paradigmatic Dissimilation
When, through sound change, elements of a grammatical paradigm start to conflate in a way that is not easily remedied through re-wording, the forms may dissimilate. For example, in modern Korean the vowels /e/ and /ɛ/ are merging for many people in the capital Seoul, and concurrently the second-person pronoun 네 /ne/ 'you' is shifting to 니 /ni/ to avoid confusion with the first-person pronoun 내 /nɛ/ 'me'.
Similarly, it appears that English she, historically heo, may have acquired its modern sh form through dissimilation from he, though it is not clear whether the mechanism was idiosyncratic sound change (palatalization) of heo, or substitution of heo with the feminine demonstrative pronoun seo.
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