Answering <Whose is this book?> with <One of my friends'>

Question

Let's say I am in a library and there is a book on the desk beside mine. If someone who works at the library or someone else studying at the library comes up to me and asks, "Do you know whose this book is" or "Whose is this book," can I answer saying either of these:

• One of my friends'.

• It's one of my friends'.

I think it would be colloquially okay to say these sentences in the context I provided instead of "It belongs to one of my friends" which is the more wordy version. Do you agree with me? I am asking this because I can hear Americans use the construction, "It is one of my friends' book" but I was just not one hundred percent sure about the construction where the object ("book") is omitted like in "It is one of my friends'."

Answer 1

You could say "one of my friends' [[book]]". In that case, the possessive clitic would be attached to the entire phrase "one of my friends".¹ However, that often sounds awkward, because it might seem as though the clitic attaches only to the last word.² Therefore, it may be better to reword the sentence, e.g.:

It is my friend's.
It belongs to one of my friends.

By the way, this issue has come up occasionally on ELL. You may be interested in this question: How to understand "waving it in the bloke from the Ministry's face" (and perhaps also this ELU question: https://english.stackexchange.com/questions/363229/adding-a-possessive-to-a-singular-noun-phrase-that-ends-in-a-plural-noun/).

---

¹ CMOS gives the example "the skull and crossbones' symbolic meaning"; in that case, the apostrophe attaches to the entire phrase "the skull and crossbones". (Chicago Manual of Style (14th edition), Chicago: University of Chicago Press, 1993, section 6.20, pg. 199.)
² For an example of how this might cause issues, consider "the king of England's territory". Is he the king of the territory, or does the territory belong to him?

Answer 2

Giving short answers to questions is very common in English.

For example, the question "Do you drive?" could be answered:

• Yes, I drive.
• Yes, I do.
• I do.
• Yes.

Short answers can be considered impolite in certain situations, but a lot depends on your tone and even facial expression. Giving 'yes or no' answers can come over as guarded - like you are only giving away minimal information. But in many contexts a positively delivered yes or no is just fine and all that may be needed.

Your suggested answer to the given question is absolutely fine. The question is about who the book belongs to, so the shortest possible answer would be the name of its owner. Instead, you're saying "one of my friends", presumably because you think they won't know your friend's name - but it could come over as if you are being evasive by concealing their name. Perhaps a more polite way to answer, still keeping it short, would be something like "my friend John's".

Answer 3

To make it the least ambiguous, I believe saying:

It belongs to a friend of mine.

Would be correct. As mentioned on Gym English:

a friend of mine: one of my friends.

It's an idiom with the exact same meaning as "one of my friends".

Another option would be to use:

It is a friend of mine's.

It would work perfectly in this context as well. "It" refers to the book, and "friend of mine's" means "one of my friends'", but less vague.

---

You could also refer to your friend's name, with:

It belongs to my friend Daniel.

Or:

It is my friend Daniel's.

This could be used if you want a more polite way of addressing your friend.