There are two main uses of the apostrophe:
1. showing possession – or –
2. showing contraction (where a letter or letters have been left out)
1. apostrophe showing possession/ used to show possession
1.a. add ‘s to singular nouns (both common and proper) and to indefinite pronouns
Bob’s friend the farm’s produce
someone’s book everyone’s vote
1.b. personal pronouns have no apostrophes in their possessive forms
For instance, the personal pronoun it does not form a possessive with an apostrophe, only with the s:
The car lost its brakes.
1.c. making names that end in “s” possessive
Is it Harris’ or Harris’s?:
This depends on your personal preference – unless you need to follow a specific style manual/ guidebook:
The Associated Press Stylebook says the correct way to write the possessive case of Harris is Harris’.
Other style guides, including the Chicago Manual of Style, say Harris’s is correct. If there isn’t a specific guidebook you need to follow, you can use either Harris’ or Harris’s.
2. apostrophe showing contraction
Contractions are two word combinations formed by leaving out certain letters which are replaced by an apostrophe. Some common contractions include
| cannot | can’t |
| will not | won’t |
| I would, I had | I’d |
| it is, it has | it’s |
3. its vs. it’s
The personal pronoun it does not form a possessive with an apostrophe, only with the s:
The car lost its breaks.
It is the third person singular pronoun used for things.
A helpful rule is that personal pronouns have no apostrophes in their possessive forms
Consider the following chart:
| Subjective | I | we | you | he | she | it | they |
| Possessive | my (mine) | our (ours) | your (yours) | his (his) | her (hers) | its (its) | their (theirs) |