Possession Adjectives are special words in English that do not take an apostrophe. There are only seven of these words. Memorize them:
my
your
her
his
our
their
its
Also note, words that sound the same but are not the same:
Your - a possession adjective.
You’re - a conjunctive meaning, "you are."
Their - a possession adjective.
They’re - a conjunctive meaning, "they are."
An apostrophe is used to indicate a missing letter or letters.
Examples (conjunctive - combination of two words):
I can’t (can not)
I won’t (will not)
It’s (it is)
I don’t (do not)
An apostrophe is used to indicate possession.
Examples:
Fisher’s campus
That purse is Sue’s
Miller’s car repair shop
If there is more than one entity in possession, the apostrophe comes after the s:
Millers’ car repair shop
Kauffmans’ bakery
The conjunctive form takes precedence over the possessive form.
If the apostrophe has been used to form a conjunctive, and the same (conjunctive word) is used to indicate possession, the apostrophe is removed to indicate possession (see rule 1 above).
Examples:
It’s time. (Meaning: It is time.)
The cat is in its cage.
Apostrophes are not used to indicate plurals.
Examples:
Wrong: Peach’s for sale.
Right: Peaches for sale.
Wrong: Business card’s designed per specification.
Right: Business cards designed per specification.
Wrong: 100’s of ways to get it done.
Right: 100s of ways to get it done.
Wrong: She has a large collection of CD’s.
Right: She has a large collection of CDs.