Most grammar books you encounter in school are prescriptive—they tell you that you shouldn't end a sentence with a preposition or that "ain't" isn't a word.
The authors categorize English into six main "varieties" based on specific factors: a university grammar of english by quirk and greenbaum pdf
Some notable features of "A University Grammar of English" include: Most grammar books you encounter in school are
If you are looking for a digital copy, you can find various versions through academic and library archives: a university grammar of english by quirk and greenbaum pdf
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