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Reading Writing Lab

Microlab 1 - Apostrophes

Even small punctuation marks are very important for writing clear and correct sentences. An incorrectly used or omitted apostrophe can completely change the meaning of a sentence. For example, “horses walk” means that horses are walking, while “horse’s walk” is talking about a walk belonging to a horse. It is important to use apostrophes correctly because they can completely change the meaning of a sentence. This microlab will help you recognize apostrophe errors and use them correctly in your own writing.

Review of Apostrophes

Apostrophes are used to form contractions (like“it’s”), possessives (like “Tasha’s”), and some plurals (like “P.O.W.’s”). Let’s review each of these uses one at a time.

I. The Apostrophe in Contractions:

“To contract” means to shorten. A contraction is a way of shortening a word or phrase by leaving out some of the letters. An apostrophe (’) is used to mark where the letters have been omitted. Contracted forms include:

I have = I’ve
cannot = can’t
he would = he’d
she would = she’d
we are = we’re
they are = they’re

The following examples show how contractions appear in complete sentences:

It is time to go. = It’s time to go.
Bob is here. = Bob’s here.
That is none of your business. = That’s none of your business.
Who is coming with us? = Who’s coming with us?

When writing contractions, be sure to use the apostrophe correctly. The apostrophe should mark the spot where letters have been left out of the contraction:

did + not
Correct : didn’t
Incorrect: did’nt
should + not
Correct: shouldn’t
Incorrect: should’nt

As you can see, the contraction drops the “o” in “not.”

II. The Apostrophe in Possessive Form:

The “possessive form” is used to show that a noun (person, place, or thing) owns another noun. Usually, the possessive form of a noun is formed by adding an ’s to the noun:

The wallet belonging to the man ---> The man’s wallet
The date of today ---> Today’s date
The books belonging to the child ---> The child’s books
The dog Jean owns ---> Jean’s dog
The house of the Johnson family ---> The Johnson’s house

Forming Possessives Correctly

III. Forming the possessive of a singular noun (one person, place, or thing):

Write the singular noun: spy
Add ‘s: spy’s

You can use the possessive form to show what belongs to the spy:

The spy’s map
The spy’s hand

IV. Forming the possessive of the singular and plural nouns ending in “s”:

Write the singular noun: Dennis
Add an apostrophe at the end of the word Dennis’

For a singular noun ending in “s,” add an apostrophe after the word to show that something belongs to it.

Write the singular noun: platypus
Add ‘: platypus’

Plural nouns (more than one person, place, or thing) ending in “s” show ownership the same way as singular noun ending in “s.”

To write the possessive form of a plural noun ending in “s”:
Write the plural noun: dogs
Add an apostrophe at the end of the word: dogs’

The possessive form is used to show what belongs to a group of dogs:

The dogs’ house
The dogs’ bone

V. Forming the possessive of plural nouns that do not end in “s”:

If the plural noun does not end in s, form the possessive by adding an ‘s:

Write the plural form: women
Then add ’s: women’s

The women’s class | The men’s sports

VI. An apostrophe is never used with possessive pronouns:

Possessive pronouns are words such as its, theirs, yours, ours, hers, and his. In the sentences below, notice how the apostrophes are used to show something belonging to a noun, but no apostrophe is used with possessive pronouns.

Juan’s part-time job used to be hers. The children’s favorite part opened its gates again. The last house on the left is ours, and my brother’s house is across the street.

It’s and its:

Its without an apostrophe is a possessive pronoun meaning “belongs to it”:
The cat licked its fur. The bird jumped on its nest.

It’s with an apostrophe is a contraction for “it is” or “it has”:

It’s supposed to rain today. It’s been a long time since we met.

If you’re unsure whether to use “its” or “it’s,” try substituting “it is” or “it has” in the sentence. If you cannot substitute these words, then you cannot use “it’s”:

The dog reached to scratch _______ fleas.

In this sentence, neither “it is fleas” or “it has fleas” make sense; therefore, no apostrophe is used.

VII. Showing ownership with an indefinite pronoun:

An apostrophe can be used to show ownership with an indefinite pronoun such as “one,” “everyone,” “someone,” “anybody,” or “anyone”:

One’s true friends remain loyal in hard times.
You can use anyone’s pass to get in.

Special Uses of Apostrophes

VIII. Use an apostrophe to form the plural of abbreviations containing a period:

Two medical doctors ---> Two M.D.’s
Five doctors of philosophy ---> Five Ph.D’s
Four prisoners of war ---> Four P.O.W.’s

IX. Do not use an apostrophe after abbreviations that do not contain periods:

She fixes TVs for a living. Two YMCAs sponsored the event. He parked the VWs in the back lot.

X. Use an apostrophe to show omitted numbers when writing the year or naming a decade:

The class of 1984 ---> The class of ‘84
During the 1970s ---> During the ‘70s
Exception: When you type out the full year, don’t use an apostrophe:

Correct: In the 1970s
Incorrect: In the 1970’s

Key Points to Remember:

  1. Use apostrophes to form contractions. The apostrophe marks the spot where letters have been omitted.
  2. Apostrophes are used to form possessives. Remember that no apostrophe is used with a possessive pronoun.
  3. Apostrophes are used to form the plural abbreviation that contains periods.
  4. Apostrophes replace numbers that are omitted from dates.