An Apostrophe to Show Ownership (Grammar Lesson)

by Craig Shrives

An Apostrophe to Show Ownership

An apostrophe and the letter s are used to show ownership.

When using an apostrophe for ownership, the first thing to consider is whether there is one owner (a singular owner) or more than one owner (a plural owner). This determines the position of the apostrophe. Here are some examples with the owners highlighted:
  • The boy's den.
    • (With one boy, the apostrophe is placed before the s. In other words, you have to add 's.)
  • The boys' den.
    • (With more than one boy, the apostrophe is placed after the s. In other words, add just '. Remember, the s will already be there.)

With a Singular Owner, the Apostrophe Is Placed before the S

When the owner is singular, add 's. For example:
  • Wagner's music is better than it sounds. (Mark Twain)
  • A friend's eye is a good mirror.

With a Plural Owner, the Apostrophe Is Placed after the S

When the owner is plural, add ' after the s. For example:
  • The dogs' dinner smells better than ours.
  • The ladies' mobile phones were confiscated until after the show.

Plural Nouns Not Ending S (Exception 1)

For plural words that do not end s (e.g., children, people, women), add 's (as though they were singular). For example:
  • Zeus does not bring all men's plans to fulfilment. (Homer, 800-700 BC)
  • All television is children's television. (Richard P. Adler)

Singular Nouns Ending S (Exception 2)

For singular words that end s (e.g., Dickens, series, Moses), add ' or 's. (You have a choice.) For example:
  • Wells's report was shockingly bad.
  • Wells' report was shockingly bad.
Useful guideline: Write it how you would say it. If you would say Wellsiz report, use Wells's. If you would say Wells report, use Wells'.

Compound Nouns (Exception 3)

For compound nouns (e.g., brother-in-law), add 's to the end regardless of whether it is singular or plural. For example:
  • My brother-in-law's help was essential.
    • (This is help from one brother-in-law.)
  • My brothers-in-law's help was essential.
    • (This is help from brothers-in-law, i.e., more than one brother-in-law.)
Read more about forming the plurals of compound nouns.

Apostrophes with Joint and Individual Ownership (A Quirk)

For joint ownership, make just the last word in the series possessive. For individual ownership, make all parts possessive. For example:
  • Peter and Paul's factories
    • (For joint ownership, only the last part is possessive.)

  • Peter's and Paul's factories
    • (For individual ownership, all parts are possessive.)
    (Without context, it will be assumed that Peter has one factory and Paul has one factory. Another construction is required if this is not the case: "Peter's factories and Paul's factories" is one option.)
Interactive Exercise
Here are three randomly selected questions from a larger exercise, which can be edited, printed to create an exercise worksheet, or sent via email to friends or students.

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See Also

Using apostrophes Apostrophes for possession Apostrophe placement rules Apostrophe after s Apostrophe after z Apostrophe before s Apostrophes for awkward plurals Apostrophes after acronyms and abbreviations Apostrophes in contractions Apostrophes in expressions like 2 years' pay and a day's notice Apostrophes used incorrectly for plurals Apostrophe exercises Apostrophes in names Apostrophe misuse Apostrophes in contractions Using brackets parentheses Using colons Using commas Using dashes Using hyphens Using quotation marks Using semicolons