One aspect of English that causes problems for many native speakers is apostrophes. Deciding when they are needed and where to put them is not always so easy. It is clear to most educated native speakers that the following sentences contain incorrect apostrophes:

• Orange's for sale at half price! (Sign in a fruit shop window)
• Where's the dog? Its time for it's walk.

But there are many situations when things are not so straightforward. For example, when referring to parts of this ESL website, should I refer to the Parents website or Parents' website? (I choose to omit the apostrophe.) However, these articles are concerned with the particular problems faced by non-native speakers in learning English, and so I want to concentrate on a different aspect of the apostrophe problem; namely the use of apostrophes to denote possession or relationship in phrases such as the boy's mother, my dog's basket, the president's jacket.

These examples are not very difficult, but what about phrases such as the car's door? Is this correct, or should we say the door of the car, or simply the car door? The native speaker doesn't usually have to worry about questions like these; she intuitively picks the correct use for the particular meaning she wants to convey, and automatically avoids any incorrect usage. So, in this case, she would probably never say the car's door (although the car's engine .. sounds OK), and she will choose one or other of the expressions depending on what she wants to say. For example:

• Car doors are made in a factory not far from where I live. (The doors of cars .. ??)
• Someone put a scratch in the door of the car today.

Quiz

Test your knowledge of this very tricky area of English by answering these questions:

• Which of the phrases in the following pairs are not correct?
  • John's computer / the computer of John
  • the cover of the book / the book's cover
  • the corner of the page / the page's corner

• Both of the following phrases are possible, but the second one is ambiguous. Why?
  • the teacher's praise / the praise of the teacher

• Both of the phrases in the following pairs are possible, but they have slightly different meanings. In what way?
  • she's a friend of my sister / she's my sister's friend
  • a child's jacket / the jacket of a child

• Which one(s) in each of the following sets of phrases is correct?
  • goat milk / goat's milk / goatmilk
  • horse meat / horsemeat / horse's meat
  • a twenty dollars bill / a twenty dollar bill / a twenty dollar's bill / a twenty dollars' bill

---

Answers

• John's computer / the computer of John
• The cover of the book / the book's cover (both possible)
• The corner of the page / the page's corner

• The praise of the teacher could mean both that the teacher was praising or being praised.

• She's a friend of my sister implies that your sister has more than one friend; whereas She's my sister's friend implies that she is the best (and only) friend of your sister.
• A child's jacket is a jacket that has been made for a child. The jacket of a child refers to a jacket belonging to a child.

• goat milk / goat's milk / goatmilk
• horse meat / horsemeat / horse's meat
• a twenty dollars bill / a twenty dollar bill / a twenty dollar's bill / a twenty dollars' bill