Friday, September 14, 2012

Double Genitive: Twice as Much Possession

Alice e-mailed me with a wonderfully tricky question:
I recently heard someone say: She is a friend of my sister's and I. This doesn't seem right. Should it be: She is a friend of my sister's and mine? Or something else? Thanks for your help with this!
This is an awesome example of how easily we can get our knickers in a twist when there are too many things going on at once. In this case, there is a compound pronoun plus something nasty called a double genitive. Many English teachers and brainiacs would get this wrong, but Alice got it right. Bravo, Alice, you smart thing!

What the heck is a double genitive? Think of it as possessive overkill. In the sentence She is a friend of my sister's, possession is signaled twice: first with the preposition 'of' and then with the apostrophe + s. It sounds terribly awkward, but the grammar is correct.

Double genitive = preposition 'of' + possessive noun or pronoun. He's a friend of my boss's. Mr. Smith is a colleague of Melanie's. She's a favorite hairdresser of ours.

Where does it all go wrong? Even people who get the double genitive right in a sentence with a single pronoun will often get confused when faced with a compound pronoun.

Let's break it down:
  1. Write the sentence twice, using simple nouns instead of the compound structure.
    She is a friend of my sister's. She is a friend of I.

    a. The first sentence is a correct use of the double genitive.
    b. The second sentence is incorrect because it includes a subject pronoun instead of a possessive pronoun.
  2. Replace the subject pronoun with a possessive pronoun.
    She is a friend of my sister's.
    She is a friend of mine That works!
  3. Then put the conjunction back together.
    She is a friend of my sister's and mine.
Correction: She is a friend of my sister's and mine.

More examples of the double genitive: 
  • She's a former teacher of mine. She's a former teacher of Sam's. >> She's a former teacher of Sam's and mine. Or: She's a former teacher of ours. 
  • He's a neighbor of my sister's. He's a neighbor of my brother-in-law's. >> He's a neighbor of my sister's and brother-in-law's.
This may look and sound dreadful, but it's correct.


  1. I've done a grammar test of The Telegraph.
    Good grammar test could you pass? -was its title. My test was 67% with 3 mistakes from 12.

    I would like to ask this mistake:
    9 .Which of these sentences is grammatically correct?
    "Are you happy with the idea of my teaching you grammar?"
    "Are you happy with the idea of me teaching you grammar?"

    What is the explanation the idea of me?

    Kati Svaby

    1. Hello,

      I would like to correct my question:
      What is the explanation of the expression:
      "THE IDEA OF ME" ?

  2. Don't you mind if I teach you?

  3. This is an awesome blog.I have bookmarked.The check sentence structure is a well known site especially made for students. In which you can get different methods of sentence making.

  4. Grammarly Cost
    Language is an important part of expressing ourselves to the whole world. It is needed while we are speaking to someone and also when we are writing something. The language that we talk often tends to have colloquialisms, and the grammar isn't always perfect. But it does reflect into our writings. Along with that, we aren't always able to write in perfect grammar.

  5. It was an amazing article. Realy helpful. Allow me to introduce myself. Myself Bilal. I'm aSEO Expert Let me know if you need any help.