Syntax
Possessive determiners (adjectives) are used in combination with a noun, playing the role of a determiner or attributive adjective. In English and some other languages, the use of such a word implies the definite article. For example, my car implies the car that belongs to me/is used by me; it is not correct to precede possessives with an article (*the my car) or other definite determiner such as a demonstrative (*this my car), although they can combine with quantifiers in the same ways that the can (all my cars, my three cars, etc.; see English determiners). This is not the case in all languages; for example in Italian the possessive is usually preceded by another determiner such as an article, as in la mia macchina ("my car", literally "the my car") or quel tuo libro ("that book of yours", literally "that your book").
Some languages place the possessive after the noun, as in Norwegian boka mi ("my book"). Here again the equivalent of the definite article – in this case the definite ending -a on the noun bok – is used in addition to the possessive.
Possessive determiners may be modified with an adverb, as adjectives are, although not as freely or as commonly as is the case with adjectives. Such modification is generally limited to such adverbs as more, less, or as much ... as (comparative) or mostly (superlative), for example in This is more my team than your team and This is mostly my team.
Possessive pronouns are generally used on their own, playing the role of noun phrases, so mine may stand for "my cat", "my sister", "my things", etc. In some languages these may require articles or other determiners, as the French le mien etc. In English, the -'s possessives formed from nouns or noun phrases (though not always called possessive pronouns) behave in the same way; the president's may stand for "the president's office", "the president's policies", etc.
A related use is that of the predicative expression, as in sentences like the book is mine. Here mine may be considered to be a predicate adjective (like red in the book is red) rather than a pronoun; in English, however, the same possessive form is used anyway. Other languages may use differing forms; for example French may use ...est à moi for "...is mine".
A particular use of possessive pronouns (and equivalent noun forms) in English is that illustrated in phrases like a friend of mine and that coat of Fred's, used to form possessive expressions when the desired determiner is something other than the default the implied in the usual possessive determiner.
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