The Apostrophe
Apostrophes are used to do the following:
1) Show possession.
2) Form the plurals of letters, numbers, abbreviations, and words used as words.
3) Indicate omitted letter and numerals.
Apostrophes Show Possession
I. An apostrophe indicates possession. Many people, however, leave off the apostrophe, which can cause a word to seem plural, not possessive.
Ex: Incorrect Correct
Titos opinion Tito's opinion
the parents child the parent's child
one days work one day's work
Follow these basic rules to avoid confusion:
1) Add an apostrophe + -s to most singular nouns and to plural nouns that do not end in -s.
Ex: Singular nouns Plural nouns not ending in -s
dog's life geese's behavior
the judge's ruling children's imaginations
Singular nouns that end in -s or -z may use either apostrophe + -s or just the apostrophe; use one form or the other consistently throughout a paper.
Ex. Ross's car or Ross' car
Oz's scarecrow or Oz' scarecrow
2) Add an apostrophe (but not an -s) to plural nouns that end in -s.
Ex. students' books guys' horses
books' pages chapels' doors
3) Indicate possession only at the end of compound or hyphenated words.
Ex. president-elect's decision
mother-in-law's temper
the Boy Scouts of America's leader
4) Indicate possession only once when two nouns share ownership.
Ex: Bonnie and Clyde's tommygun
John and Paul's album
But when ownership is separate, each noun shows possession
Ex: Bonnie's and Clyde's hairstyles
Stalin's and Truman's countries
II. Use an apostrophe to form the plural of letters, numbers, abbreviations, and words cited as words.*
*EXCEPTION TO THIS RULE: An apostrophe is not required when forming the plural of an abbreviation or a number. (Ex: VCRs, TVs, 1830s, 60s)
Ex: Your m's look like your w's.
Count to 333 by3's. (Also 3s or threes)
Most banks have ATM's. (Also ATMs)
I've heard enough of your no's for a while.
III. Use an apostrophe to indicate omitted letters or numbers in contractions.
Ex: I'm (I am) Guns 'n' Roses (Guns and Roses)
TP'd (toilet papered) the flood of '85
CAUTION: DO NOT use an apostrophe with personal pronouns (my, your, his, her, our, their, its, etc...).
Hint: Remember that it's and who's are contractions for it is and who is, and shouldn't be confused with the possessive pronouns its and whose.