How to Use Apostrophes

Punctuation is an essential component of the English language that clarifies how words and phrases relate to each other. One of the few types of punctuation that can be used within words to change their meaning and clarify their relationship to other words is the apostrophe. An apostrophe (‘) can serve two purposes: to signify ownership or possession and to replace letters in contractions. There are different rules for how apostrophes are used in writing, depending on the situation.

Plural vs Possessive

Because plurals and possessives are often pronounced the same, they are easily confused. A plural word is a word that indicates more than one of something. A possessive word is a word that indicates ownership or possession. Plural vs possessive word forms are used in entirely different situations. The key distinguishing factor is that non-possessive plural words will not have an apostrophe while most possessive words will have an apostrophe to show possession.

A possessive noun usually means the same thing as the object of the noun. To form a singular possessive noun, an apostrophe followed by an “s” is added to the end of the word. For example, to write “the use of the word” as a possessive noun, this would be “word” plus an apostrophe plus an “s,” which would look like this: “word’s use.”

In some cases, the noun might end in an “s.” In these cases, it is acceptable to format the possessive noun the same way that one might format a noun without an “s”: “bus’s wheels.” However, depending on what style guide is used, possessive nouns that end in “s” can also be formatted with just an apostrophe after the word, not another “s,” since the “s” is redundant:” “bus’ wheels.” Since plural words usually end in “s,” this format is also used for most plural possessive words. When a family name is possessive, the name should have an “s” then an apostrophe at the end of the name. For example, if the Wallace family had a pet parrot, one would write, “The Wallaces’ pet parrot was colorful.”

Again, these formats vary depending on the style guide or instructor preferences. For example, MLA (Modern Language Association) style requires an “s” after the apostrophe for plural possessive words that end in “s” but not for singular possessive words that end in “s.” In some style guides, the preference is that an “s” is always included after the apostrophe for any possessive noun unless the next word starts with an “s,” such as “iris’ size” or “iris’s color.” Below is a chart of some singular and plural possessive words with their base form and their possessive form.

Incorrect apostrophe usage for plural words since apostrophes show possession

Correct apostrophe usage since this is the market belonging to Bahnhof

Possessive Pronouns

As a rule, possessive nouns always require an apostrophe to indicate possession. However, possessive pronouns, words that stand in the place of nouns, do not. The possessive pronouns are:

• mine,
• ours,
• yours,
• his,
• hers,
• its,
• and theirs.

All of these words are possessive, but none of the words are formatted with apostrophes because they are pronouns rather than nouns. For example, instead of “her’s dog,” one would simply write, “her dog” because the word is already possessive.

Apostrophe Rules for Joint Possession

Adding an apostrophe and “s” is how to show possession in situations that discuss something belonging to one person or thing. However, there are cases when multiple things belonging to multiple people are discussed or when a group of people collectively own something. There are rules that cover these situations that require certain placement of the apostrophe that is showing ownership. The first situation is joint possession: this is when two or more people own something collectively. In these cases, an apostrophe and “s” is only added after the last person in the list. For example, if Amy and Ari have a dog together, it would be “Amy and Ari’s dog.” On the other hand, if one is writing about multiple things that multiple people own, an apostrophe and “s” is placed after each person’s name in the list. For example, if David and Daniel went on vacation and each packed their own suitcase, one could write that “David’s and Daniel’s suitcases were in the trunk of the car.”

Examples of Apostrophes for Possessive Nouns

The following list includes some examples of using apostrophes, both for singular and plural words, to show possession in sentences:

• “Mary’s dog enjoyed running at the park.”
  • “Mary” is a singular noun, so adding an apostrophe and “s” makes it possessive.
• “The three cats’ toys were all over the house.”
  • “Cats” is a plural noun that ends in “s,” so simply adding an apostrophe makes it possessive.
• “The children’s drawings were displayed on the teacher’s refrigerator.”
  • “Children” is a plural noun, but since it does not end in “s,” an apostrophe and an “s” are required to make it possessive; “teacher” is a singular noun, so adding an apostrophe and “s” makes it possessive.
• “The Smiths’ house had ten bedrooms.”
  • “Smith” is a family name, so an “s” and an apostrophe are added to make it possessive.
• “John’s and Jay’s dogs were playing in the living room floor when John went over to visit.”
  • One of the dogs belongs to John and one of the dogs belongs to Jay, so both “John” and “Jay” take an apostrophe and “s” to indicate separate ownership.
• “Alex and Sam’s children were their pride and joy.”
  • The children belong jointly to both Alex and Sam, so only the last person in the list (Sam) receives an apostrophe and “s” to indicate joint ownership.

Apostrophe Use: Contractions and Omissions

In the cases above, apostrophes are used to indicate possession or ownership. However, there is one more instance when apostrophes are used in writing. This is with contractions, words that combine multiple words into one and omit letters. In contractions, an apostrophe is usually added where the letters were omitted to show distinction in its meaning. For example, instead of writing “do not,” a contraction of this would be “don’t.” In this case, the apostrophe is placed where the “o” in “not” was omitted when the words were combined. Here is a chart with several other examples of contractions, including the often confused “it’s”: while “its” without an apostrophe is possessive, “it’s” with an apostrophe is a contraction meaning “it is.”

Lesson Summary

The apostrophe, which looks like a single quotation mark (‘), is commonly used to show possession or ownership in writing. Both plural and possessive words often end in “s.” However, plural nouns, which indicate there is more than one of something, do not have apostrophes. Possessive nouns, on the other hand, which indicate ownership or possession, always have apostrophes usually followed by an “s.” This means the difference between more than one dog, or “dogs,” and something belonging to a dog, or “dog’s.”

There are cases when the standard format of noun plus apostrophe plus “s” is not used:

• with nouns ending in “s,” usually just an apostrophe, not an extra “s,” is added, depending on the style guide;
• in possessive pronouns (such as “mine,” “yours,” and “theirs”), no apostrophe or “s” is added since the words are automatically possessive;
• in cases of joint possession, where two or more people own something together, only the last person in the list takes an apostrophe and “s”;
• and in cases of separate ownership where a group of things contains separate items that belong to separate people, each person in the list takes an apostrophe and “s.”

In addition to possession, apostrophes are also used in contractions, which are two or more words combined into one. The omitted letters are usually replaced with the apostrophe, like “can’t” instead of “cannot.”