Diglossia
According to some contemporary Brazilian linguists (Bortoni, Kato, Mattos e Silva, Perini and most recently, with great impact, Bagno), Brazilian Portuguese may be a highly diglossic language. This theory claims that there is an L-variant (termed "Brazilian Vernacular"), which would be the mother tongue of all Brazilians, and an H-variant (standard Brazilian Portuguese) acquired through schooling. L-variant represents a simplified form of the language (in terms of grammar, but not of phonetics) that could have evolved from 16th century Portuguese, influenced by Amerindian (mostly Tupi) and African languages, while H-variant would be based on 19th century European Portuguese (and very similar to Standard European Portuguese, with only minor differences in spelling and grammar usage). Mário A. Perini, a Brazilian linguist, even compares the depth of the differences between L- and H- variants of Brazilian Portuguese with those between Standard Spanish and Standard Portuguese. However, his proposal is not widely accepted by either grammarians or academics. Milton M. Azevedo wrote a chapter on diglossia in his monograph: Portuguese language (A linguistic introduction), published by Cambridge University Press in 2005.
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