What part of speech is "my" in the sentence?

Question

This is my book.

What part of speech is "my" in the sentence above?

This may be considered a silly question to ask, but I have referred to some dictionaries such as Word Master and Oxford's Advanced Dictionary. They consider it a determiner or possessive determiner.

The Wren and Martiner's grammar book considers it a possessive adjective because the word "my" qualifies the noun "book"

I have searched on Google to know which part of speech "my" is.

I here with provide the link which does not clarify my doubt.

I would like you to clarify my doubt: http://partofspeech.org/what-part-of-speech-is-my/.

Is " my" a pronoun, a determiner or an adjective in the sentence?

I think it is a pronoun.

Answer 1

Hmm… not even grammarians agree which part of speech is my in “my book”

• Possessive determiners constitute a sub-class of determiners which modify a noun by attributing possession (or other sense of belonging) to someone or something.

• They are also known as possessive adjectives, although the latter term is sometimes used with a wider meaning.

• Examples in English include possessive forms of the personal pronouns, namely: my, your, his, her, its, our and their, but excluding those forms such as mine, yours, 'ours, and theirs that are used as possessive pronouns but not as determiners.

• The words my, your, etc. are sometimes classified, along with mine, yours etc., as possessive pronouns or genitive pronouns, since they are the possessive (or genitive) forms of the ordinary personal pronouns I, you etc.

• However, unlike most other pronouns, they do not behave grammatically as stand-alone nouns, but instead qualify another noun – as in my book (contrasted with that's mine, for example, where mine substitutes for a complete noun phrase such as my book).

• For this reason, other authors restrict the term "possessive pronoun" to the group of words mine, yours etc. that substitute directly for a noun or noun phrase.

• Some authors who classify both sets of words as "possessive pronouns" or "genitive pronouns" apply the terms dependent/independent or weak/strong to refer, respectively, to my, your, etc. and mine, yours, etc.

• For example, under this scheme, my is termed a dependent possessive pronoun and mine an independent possessive pronoun.

Wikipedia

Answer 2

"My" is an adjective. In your example, it modifies the word "book". Specifically, it is a possessive adjective. It is also a pronoun. These things are not mutually exclusive.

Answer 3

Let's start with the demonstrative pronouns, this, that, these, those. These work like pronouns should--they can replace a noun.

I wanted the candy.

I wanted that.

They also can work another way--similar to articles, they can go in front of a noun.

I wanted that candy.

This function is called the "determiner" - it tags a noun with information that clarifies which X you are talking about. Articles and other words are determiners.

All possessive pronouns change form when used as a determiner except his.

This is mine -> This is my candy.

This is yours -> This is your candy.

This is hers -> This is her candy.

This is his -> This is his candy.

This is theirs -> This is their candy.

This is ours -> This is our candy.