Apostrophe Rules

Apostrophe Rules
  • Use apostrophes to make nouns possessive.
  • Use apostrophes to show where letters are missing in contractions.
  • Occasions when you might think you need an apostrophe but you really don’t…

Apostrophes are used to create possessive nouns—or more correctively to turn nouns into adjectives. Adjectives modify (give more information about) nouns, so possessive nouns are actually adjectives that answer the adjective question “whose?”


Singular possessive:  ____’s

the building’s history   “the building’s” tells us whose history
Iceland’s climate
an actor’s fans
the computer’s hard drive


Regular plural possessive: _____s’

several clients’ requests
the puppies’ toys
in three days’ time
the reporters’ questions


Irregular plural possessive ______’s

children’s books
the mice’s cages
the men’s hats


Joint possession (N1) and (N2)’s      

Ben and Jerry’s ice cream
Harry, Ron, and Hermione’s plan


Individual possession

Caitlyn’s, Cathy’s, and Celia’s bikes


Nouns that end in S

the engine of the bus ⇒ the bus’s engine
the cat belonging to Mr. Willis ⇒ Mr. Willis’s cat
the legislature of Kansas ⇒ Kansas’s legislature
the house belonging to the Jones family (the Joneses) ⇒ the Joneses’ house


Special note about possessive pronouns:  No apostrophe!

belonging to her ⇒ hers
belonging to him ⇒ his
belonging to it ⇒ its
belonging to them ⇒ theirs
belonging to whom? ⇒ whose?

Contracted verbs:

is ⇒ 's 
The cat’s on the bed.   There’s no one in the office.   The boy’s eating ice cream. 
are  ⇒ ‘re    am ⇒ ‘m    will ⇒ ‘ll   have ⇒ ‘ve   had ⇒ ‘d
it is ⇒ it’s;  he is ⇒ he’s;  she is ⇒ she’s;  who is ⇒ who’s
they are ⇒ they’re; we are ⇒ we’re; you are ⇒ you’re
I am ⇒ I’m   I will be ⇒  I’ll be;  


Contracted had or would: (N)’d

I had gone ⇒  I’d gone
he would go ⇒ he’d go


Contracted NOT: (V)n’t

do not ⇒ don’t
did not ⇒ didn’t
will not ⇒ won’t
are not ⇒ aren’t (etc.)


Special note about it:  it is ⇒ it’s    belonging to it ⇒ its


Other kinds of contractions

            1980s ⇒  ’80s

            rock and roll ⇒ Rock ’n’ roll or Rock ‘n roll

            because ⇒  ’cause

Plural symbols:  #s, *s

Plural numbers:  in the 1980s, count by 10s, 2x4s

Plural capital letters: As, Bs, Cs        


But do use an apostrophe to make lower case letters plural to prevent confusion:

m & m’s


Have you ever heard this phrase?  “Mind your p’s and q’s!”  It means “mind your manners” or be careful how you behave.