Pronouns and adjectives

[RaffaeleM39]

I am reading Chapter 7 of Manhattan Sentence Correction book. It is called "pronoun" but it seems to use some adjectives.
For example

"The most common pronoun mistakes involve the singular it and its, and the plural they, them and their. Whenever you see one of those five pronouns ...."

But "their" and "its" are possessive adjectives, not pronouns, right? See here

Also in the problem set:

"All students need his or her own copy of the textbook in order to take the class"

"His" and "here" are adjectives, right?
The correct phrase would be
"All students need their own copy of the textbook in order to take the class"

They seem adjectives bu acting like pronouns because they have an antecedent. I am a bit confused about it. Instead other adjectives do not have antecedent ("The white cat is outside")

EDIT: Also in the solutions it says "our is a pronoun, but first persons pronouns never have antecedents in the sentence". Isn't our a possessive adjective?
The phrase is:
"Our cat is cuter than the cats in the shelter"

[Sage Pearce-Higgins]

Your post shows the danger of mixing up sources when studying for the GMAT! Although the British Council is a respectable source, it's odd that they describe 'his' and 'her' as possessive adjectives. They are usually described as possessive pronouns. In any case, we're interested by the way language functions, not the terminology.

For our purposes 'his' and 'her' need to refer to a noun in the sentence to make the meaning clear. That's a rule GMAT sticks to tenaciously. I can see why you found it confusing that they're called adjectives, as regular adjectives such as 'white' and 'amazing' don't have antecedents. Clearly, 'his' is related to 'he', and 'her' to 'she', etc. This is why we deal with them as pronouns.

You should know that there's lots of controversy about how to describe language and there different books can use different terminology. I would recommend that you stick to the Foundations of Verbal and Sentence Correction books. We've tried to distill all the important things to know about GMAT, using the minimum jargon.