The Basics of Using the Apostrophe to Show Possession

The apostrophe is typically used to signal that one thing "belongs to" or is a part "of" another.

EXAMPLE:
the dancer's outfit (the outfit belonging to the dancer)
the warranty's expiration (the expiration of the warranty)

1. How do I know when I need an apostrophe to signal possession?

• Two or more nouns appear together, usually right next to each other.
  the dancer's outfit (the outfit belonging to the dancer)
  the warranty's expiration (the expiration of the warranty)
  
  
• The first noun ends in "s."
  THIS: the dancer's outfits
  NOT: the dancer with the outfits
  
  
• The phrase can be "unpacked," using "belonging to" or "of"
  EXAMPLES:
  the dancer's outfits = the outfits belonging to the dancer
  the warranty's expiration = the expiration of the warranty
  

2. How do I know where to put the apostrophe?

• The apostrophe is always attached to the first noun.
  THIS: the dancer's outfits
  NOT: the dancers outfit's
  
  
• To decide whether the apostrophe should be placed before the final "s" or after the final "s," UNPACK the phrase--re-write the phrase using "belonging to" or "of."
  
  EXAMPLE:
  the dancer's outfits = the outfits belonging to the dancer.
  (Notice: there is no "s" after "dancer" in the unpacked version)
  
  EXAMPLE:
  the dancers' outfits = the outfits belonging to the dancers
  (Notice the "s" at the end of "dancer" in the unpacked version).
  
  In other words, whether the apostrophe belongs before or after the "s" depends upon your intended meaning. In the examples here, if the outfits belong to only one dancer, then the apostrophe is put before the "s." If the outfits belong to more than one dancer, then the apostrophe is put after the "s."

3. So, is this everything I need to know about apostrophes?

• Wouldn't that be nice. Apostrophes also are used to signal contractions (e.g., can't = cannot).
  
• Even to show possession, there are enough times when the situation is more complicated than what we have outlined that style manuals have developed guidelines for using the apostrophe. Check out the Longman Handbook for Writers and Readers or the Ready Reference Handbook (both available in the Writing Center) for a more in-depth analysis.