Prescriptive and descriptive grammar.
We call prescriptive grammar one that not only describes the rules of the functioning of language but distinguishes between a "pure" language, to follow and forms to avoid as erroneous.
We call descriptive grammar one that illustrates the operation of a language mechanisms without indicating a "purity", but presents these mechanisms as subject to change in space and time.
Our grammar is inspired by this second model, in an attempt to help students of Italian as a second language to orient themselves in the often discordant forms of Italian spoken in the various Italian regions or by members of different social classes, or written in the present and past literature, etc...
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