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Study skills

• Study support
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• Study skills

Apostrophes

• Part 1: When to use apostrophes
• contraction
• ownership
• singular nouns
• plural nouns ending in s
• plural nouns not ending in s
• Part 2: When not to use apostrophes
• Common mistakes
• for plurals
• it’s and its
• you’re and your
• with shortened forms – FAQs not FAQ’s
• with decades – 1990s not 1990’s
• Useful resources

Part 1: When to use apostrophes

The correct use of apostrophes can be difficult. Many people are unsure of when to use them, sometimes adding apostrophes when they’re not needed and at other times leaving them out when they should be used!

Apostrophes are used for only two purposes. These are to indicate:

• contraction
• ownership

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Contraction

The term 'contraction' refers to the shortening of a single word or two words that are adjacent (next to each other). When two adjacent words are joined together and contracted an apostrophe is used to indicate the omission of one or more letters.

She’s studying for the exam. = She is studying … I’d like to finish my assignment before next Friday. = I would like… He’ll be at the lecture. = He will be Other examples: I’m going to the library. = I am going … She’ll give a presentation. = She will give … He’d finished the paper. = He had finished … We’ve started our research. = We have started … You’re expected to read widely. = You are expected …

Point to note
Contractions are NOT generally used in formal academic writing, for example, the reports and essays that students are required to write at university. Contractions are informal and conversational and they do not convey the appropriate formal academic tone generally required for university assignments.

Ownership

The other use of apostrophes is to show ownership (possession) or association.

a. Ownership - singular nouns

To show ownership or association for singular nouns:

• write the singular and
• add an apostrophe followed by s – (’s)

The lecturer’s explanation was clear.                    the explanation given by the lecturer  - write the singular (lecturer) and  - add an apostrophe followed by s (lecturer’s) Other examples: The student’s books were expensive. = the books belonging to the student I took note of the tutor’s comments regarding the exam. = the comments made by the tutor

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Other uses of the apostrophe followed by s (’s):

• Personal names ending in s

There are various and complex rules that are sometimes applied for personal names ending in s. The Style manual ¹ recommends for simplicity that an apostrophe followed by (’s) should be added to any personal name ending in s to show ownership or association:

e.g. Professor Collins’s book (the book belonging to or written by Prof. Collins)
       Dr Saunders’s lecture (the lecture presented by Dr Saunders)
 

• Joint ownership

An apostrophe followed by s (’s) is used on only the second of the two ‘owners’.
e.g. Ben and Nam’s assignment, i.e. the assignment jointly done by Ben and Nam

In contrast, where ownership is not joint, each owner takes an apostrophe.
e.g. the lecturer’s and the tutor’s comments, i.e. the comments of the lecturer and the comments
of the tutor

b. Ownership - plural nouns ending in s

Most nouns form their plural by adding s.
To show ownership or association of plural nouns ending in s:

• write the plural and
• add an apostrophe after the s (s’)

Students’ results will be released on Friday.              the results of more than one student  - write the plural (students) and  - add an apostrophe after the s (students’)

c. Ownership – plural nouns not ending in s

To show ownership or association for plural nouns that do not end in s:

• write the plural and
• add an apostrophe followed by s - (’s)

singular   -  plural  NOT ending in s    man                men woman           women The assignment required us to discuss men’s attitudes to women’s changing roles.                                                                                                                                                          attitudes of men     roles of women - write the plural (men) (women) and  - add an apostrophe followed by s (men’s) (women’s)

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Summary
singular
                tutor’s comments = comments of one tutor
                lecturer’s expectations = expectations of one lecturer

plurals ending in s
                tutors’ comments = comments of more than one tutor
                lecturers’ expectations = expectations of more than one lecturer

plurals not ending in s
                men’s attitudes = attitudes of more than one man
                women’s roles = roles of more than one woman

Part 2: When not to use apostrophes

Common mistakes

1. Apostrophes are often mistakenly used for plurals.

Apostrophes are never used to indicate simple plural, i.e. more than one of any item.

She returned the books to the library.                          (books NOT book’s or books’) Good students usually arrive early for lectures.          (students NOT student’s or students’)                                                                                    (lectures NOT lecture’s or lectures’) It is important to contribute at tutes.                            (tutes NOT tute’s or tutes’)

Hint
If you’re not sure whether a word ending in s needs an apostrophe, try substituting her, his, its or their for the word ². If it makes sense, it needs an apostrophe; if it does not make sense, no apostrophe should be used.

the lecturer’s explanation – her explanation = the explanation given by the lecturer                     This makes sense and therefore the word lecturer needs an apostrophe. However: Students conducted a survey – Their conducted…                This does not make sense and therefore no apostrophe is used with the word students. (It is a simple plural and does not indicate ownership or association.)

2. Many people confuse it’s and its.

It’s is only ever used as a contraction for it is (see below) and for it has in examples such as: It’s (it has) been decided to postpone the tutorial.

• Its stands for belonging to or associated with it.

At university it’s important to submit each assignment by its due date.                                                                                                               it is                                        the due date for each assignment A good way to avoid confusing these two is to remember that the word its indicates possession in the same way as, for example, the words my, your, his, her, our and their do. These words do not have apostrophes and, in the same way, neither does its – belonging to it.                       my           – belonging to me                 your        – belonging to you                 his          – belonging to him                 her          – belonging to her                 our          – belonging to us                 their        – belonging to them                 its           – belonging to it

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3. Your and you’re are also frequently confused.

They sound alike but their meanings are entirely different.

• your means belonging to or associated with you.
• you’re is a contraction of you are.

You’re expected to keep up-to-date with your reading at university.                                                                    contraction of ‘you are’                 the reading you are required to do

4. Apostrophes are often incorrectly used with shortened forms.

DO NOT use an apostrophe for plurals of shortened forms.
e.g. FAQs not FAQ’s
         CDs not CD’s

5. DO NOT use an apostrophe when referring to decades.

e.g. the 1970s, the 1990s, etc.
The 1960s was a time of idealism among university students.

Useful resources

Style manual for authors, editors and printers, 6th edn, 2002, rev. Snooks & Co., John Wiley & Sons, Milton, Qld.

(Chapter 6 – Spelling and word punctuation; Chapter 7 – Sentence punctuation.)