Question

what is exactly the purpose of a detminer​

Answer 1

Determiners are important because they work to clarify nouns and make a sentence as precise and focused as possible. Many parts of speech, such as articles, demonstratives, quantifiers, and possessives, can act as a determiner.

Determiners are used to identify things in further detail. To take the dictionary definition, they are modifying words that determine the kind of reference a noun or noun group has. ... They are used in front of nouns to indicate whether you are referring to something specific or something of a particular type.

Answer 2

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A determiner, also called determinative, is a word, phrase, or affix that occurs together with a noun or noun phrase and serves to express the reference of that noun or noun phrase in the context. 

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