Punctuation

Use as little punctuation as necessary while retaining the meaning of the sentence.

Apostrophe 

to indicate possession
Use ’s after singular nouns, plural nouns which do not end in s and indefinite pronouns.
DO    Frank’s book
DO    anybody’s guess
DO    The children’s play area is next to the café’s toilet.
Use just ’ after plural nouns ending in s.
DO    Strong tea is sometimes called builders’ tea.
DO    The student was awarded the Examiners’ Prize.
 
If a name already ends in s or z and would be difficult to pronounce if ’s were added to the end, consider rearranging the sentence to avoid the difficulty.

DO    James’s teaching methods were popular with the students.     OR
The teaching methods of James were popular with the students.    ORJames was a popular teacher, thanks to their teaching methods.

In compound nouns and where multiple nouns are linked to make one concept, place the apostrophe at the end of the final part (and match it to that noun).

DO    the Archbishop of Canterbury’s tortoise
DO    my mother-in-law’s dog
DO    his step-brothers’ dinners

Do not use an apostrophe in its with the meaning ‘belonging to it’ (this is analogous with his/hers/theirs): note that it’s is a contraction of ‘it is’.

DO    The cat has been out in the rain and its paws are muddy.
DO    The cat has been out in the rain and it’s muddy.
DON’T    The cat has been out in the rain and it’s tail is wet.

Some place names have an apostrophe and some don’t – this can’t be predicted and must be checked.
DO    All Souls College
DO    Earls Court
DO    St Peter’s College
DO    Land’s End
DO    University of St Andrews

Some street names have an apostrophe (usually linked to saints’ names from nearby churches); these are also idiosyncratic.

DO    There is a famous pub on St Giles’.
DON’T    St Giles’s splits into Woodstock and Banbury Roads.
DO    Christ Church is on St Aldate’s.
DO    St Michael’s Street is a through road for bicycles.

Use apostrophes with noun phrases denoting periods of time (use an apostrophe if you can replace the apostrophe with ‘of’).

DO    He took a week’s holiday [holiday of a week].
DO    You must give 3 months’ notice [notice of three months].
DO    It will arrive in 3 weeks’ time.
DO    It will arrive in 3 weeks.
DON’T    It will arrive in 2 months time.
But do not use an apostrophe in adjectival phrases.
DO    She was 8 months pregnant when she went into labour.
DO    It arrived 12 weeks ago.
DON’T    He is 3 years’ old.

to indicate that letters have been omitted (contractions)

Use an apostrophe in the position the omitted letters would have occupied, not where the space was between the original words.

DO    I don’t like cheese. [=do not]
DON’T    I do’nt like cheese. [≠do not]
DO    He wouldn’t do that.

Do not use an apostrophe before contractions accepted as words in their own right.
DO    He is on the phone.
DO    He had swine flu.
DON’T    There is no vaccine for all types of ‘flu.

Do not use an apostrophe to make a plural, even with a word/phrase that is not usually written in the plural or which appears clunky. All of the following examples take an ‘s’ as normal in English to make their plurals.
DON’T    Three video’s for a tenner.
DON’T    I trust all the MP’s.
DON’T    Clothes were colourful in the 1970’s.
DON’T    CD’s are all but obsolete.
DON’T    This is a list of do’s and don’t’s.
DON’T    We invited several VIP’s.

To clarify something which will look odd if an s is added, consider italicising it or placing it in single quotation marks, or rewording it.

DO    Subtract all the xs from the ys.
DO    Dot the ‘i’s and cross the ‘t’s.
DO    A list of dos and don’ts. [or  A list of dos and don’ts.]

Brackets

parentheses/round brackets ( )

Use in place of a pair of dashes or commas around a non-defining phrase (one which adds extra information, a translation, dates, an explanation or a definition).

DO    The library (which was built in the seventeenth century) needs to be repaired.
DO    It was (as far as I could tell) the only example of its kind.
DO    Magdalen College (founded in 1458) has a herd of deer.
DO    The tactic of Blitzkrieg (which means ‘lightning war’ in German) was used in the invasion of Poland in 1939.
DO    Preheat the oven to 350°F (180°C).
using other punctuation with brackets

Include full stops/exclamation marks/question marks/quotation marks before the closing bracket only if the complete sentence/quote is in brackets; otherwise, punctuate after the closing bracket.
DO    The last bus today is at 16:45 (which is earlier than usual).
DO    The last bus today is at 16:45. (That’s earlier than usual.)
square brackets [ ] 

Use to enclose comments, corrections, references or translations made by a subsequent author or editor.

DO    An article referring to the restrictions placed by some airlines on the appearance of cabin crew stated that even footwear was proscribed [sic].
DO    I have been responsible in the real sense, that I have had the blame for everything that has gone wrong. [Laughter and cheers.]
DO    This was quoted by Brown [1940, Chicago].
angle brackets < > and curly brackets { } 
These are used for technical purposes – only use them in the correct context.

Bullet points

Don’t punctuate the end of bullet points which are a list of items.
DO    Recycling depot areas:

• Household waste
• Commercial and trade waste
• Donations

If the bullet points form a complete sentence with preceding text, add a full stop to the end of the last point.

DO    The following items must not be put in your food waste caddy:

• compostable cups
• glass
• non-food products
• plastic packaging.

If text inside the bullet point is a complete sentence in its own right, add a semicolon to the end of each point, ‘or’ or ‘and’ (depending on the sense of your sentence) to the end of the penultimate point, and a full stop to the end of the last one.

DO    The following will be considered good reasons for missing the final meeting of the year:

• there was a postal strike. This only applies if the postal strike took place before the date of the meeting and if you have not signed up for email alerts;
• you are absent as a result of illness;
• there is something more interesting happening elsewhere which you would rather attend; or
• you have obtained a ticket for this year’s Romanes Lecture.

Colon and semicolon

Use a colon to introduce a subclause which follows logically from the text before it, is not a new concept and depends logically on the preceding main clause.

DO    When I was young, I went on two holidays: to the Lake District and to Cornwall. 
DO    A new drink was introduced to Britain: tea.
DO    We were in trouble this time: the lid had come right off.
DO    There are two parts to this sentence: the first part, which precedes the colon, and the second part, which doesn’t.

Do not use a colon if the two parts of the sentence are not logically connected.

DON’T    We were in trouble this time: we’d never been in trouble before.

Use a semicolon to link two related parts of a sentence, neither of which depends logically on the other and each of which could stand alone as a grammatically complete sentence.

DO    The best book is the one you enjoy; the worst book is the one you hate.
DO    It is a far, far better thing that I do, than I have ever done; it is a far, far better rest that I go to, than I have ever known.
 
Use semicolons in place of commas in a complicated list or sentence if it will improve clarity, particularly if items in the list already include commas.

DO    We plan to review the quality of the research of the department, including its participation in interdepartmental, interdivisional and interdisciplinary activities; its research profile and strategy; and future challenges and opportunities.
DO    I visited the Ashmolean Museum, Oxford; the Victoria and Albert Museum, London; and the Pencil Museum, Keswick.

Comma

Use a pair of commas to surround a non-defining clause (one which adds descriptive information but which can be removed without losing the meaning of the sentence) – note that only ‘which’ or ‘who’ can be used in this type of clause, not ‘that’.

DO    The library, which was built in the 17th century, needs to be repaired.
DO    The builder, who climbed up the ladder, reached the top of the tower.
Do not use commas to surround a defining clause (which cannot be removed without losing the meaning of the sentence) – note that ‘which’ or ‘who’ can be replaced by ‘that’ in this type of clause.
DO    The library which was built in the 17th century needs to be repaired [but the library which was built in the 18th century does not].
DO    The builder that climbed the tower using the ladder reached the top of the tower [but the other builder who did not have a ladder could not reach the top].
DO    He asked his friend Sam to be his second [he has other friends, but he didn’t ask any of them].

Use commas to surround a non-defining word or phrase (which adds information but could be omitted without changing the sense of the sentence); follow the non-defining word/phrase with a single comma if it is at the start of the sentence.

DO    Shakespeare, the prolific playwright, might not have existed.
DO    A prolific playwright, Shakespeare might not have existed.
DO    He asked Sam, his friend, to be his second [not the Sam who is his barber].
Do not use a comma where defining information is used at the start of a sentence.
DO    The prolific playwright Shakespeare might not have existed.
DON’T    The prolific playwright, Shakespeare might not have existed.
DO    His friend Sam was his second.
DON’T    His friend, Sam was his second.

Defining vs non-defining information

Do not use a comma to join two main clauses, or those linked by adverbs or adverbial phrases (eg ‘nevertheless’, ‘therefore’, ‘however’). This is sometimes referred to as ‘comma splicing’. Either use a semicolon or add a co-ordinating conjunction (eg ‘and’, ‘but’, ‘so’). 
DO    Shakespeare was popular, and his plays were all profitable.
DO    Shakespeare was popular; his plays were all profitable.
DON’T    Shakespeare was popular, his plays were all profitable.
 
Use a comma after an introductory adverb, adverbial phrase or subordinate clause; or use a pair of commas surrounding it if it is in the middle of a sentence.

DO    However, it was too late for that.
DO    It was, however, too late for that.
DO    With his possessions in a bundle, Dick Whittington walked to London.
DO    Dick Whittington, with his possessions in a bundle, walked to London.
Do not use a comma after a time-based adverbial phrase.
DO    After playing tennis all day she was tired.
DO    Whenever she went to the cinema she ate popcorn.
DO    In 2020 the most popular game among children was hopscotch.

Use a comma between multiple qualitative adjectives (those which can be used in the comparative/superlative or modified with ‘very’, ‘quite’ etc).

DO    The sea turtle was a small, adaptable, patient creature with a colourful, tough shell.

Do not use a comma between multiple classifying adjectives: absolutes which either are or are not, such as ‘unique’, ‘English’, ‘black’ etc (although note that stylistically these can be modified).

DO    The whale saw a beautiful Caribbean coral reef.
DO    The 18th-century sandstone tower is lit up at night.
Do not use a comma between classifying and qualitative adjectives.
DO    I could see the huge Indian ocean with shallow turquoise edges.

Use a comma between items in a list.

DO    They ate fish, shrimp, plankton and krill.
DO    Today I saw jellyfish, seals, dolphins and whales.

Note that there is no comma between the penultimate item in a list and ‘and’/‘or’, unless required to prevent ambiguity – this is sometimes referred to as the ‘Oxford comma’. However, always insert a comma in this position if it would help prevent confusion.

DON’T    He took French, Spanish, and Maths GCSEs.
DO    I ate fish and chips, bread and jam, and ice cream.
DO    We studied George III, William and Mary, and Henry VIII.
DON’T    She left her money to her cousins, William and Amanda. [ambiguity regarding whether the named people are her cousins]
 

Dashes and hyphens — – -

m-dash (—)

Do not use; use an n-dash instead.

n-dash (–)

Use in a pair in place of round brackets or commas, surrounded by spaces.
DO    It was – as far as I could tell – the only example of its kind.
DO    The library – which was built in the 17th century – needs to be repaired.
Use singly and surrounded by spaces to link two parts of a sentence, in place of a colon.
DO    The bus was late today – we nearly missed the lecture.
 
Use to link concepts or ranges of numbers, with no spaces either side.
DO    German–Polish non-aggression pact
DO    The salary for the post is £25,000–£30,000.
DO    Radio 1 is aimed at the 18–25 age bracket.
Use between names of joint authors/creators/performers etc to distinguish from hyphenated names of a single person.
DO    Lennon–McCartney compositions
DO    Superman–Batman crossover comics

hyphen (-)

When to use a hyphen

In an adjectival phrase before a noun 
DO    An up-to-date list has now been published.
DO    The value of a first-class degree is indisputable.
DO    a hot-air balloon
DO    ‘Rethinking provincialism in mid-nineteenth-century narrative fiction: Villette from our village’
DO    The Department for Continuing Education offers many part-time courses.
In an adjectival phrase including a verb participle 
DO    The jumper was tight-fitting.

With prefixes only if required to avoid confusion/mispronunciation, such as where prefixes themselves or letters are repeated

DO    predynastic Egypt
DO    gifts of pre-eminent objects and works of art to the nation
DO    The animals are re-released into the wild when recovered.
DO    A protein precursor can also be called a pro-protein.
DO    Procapitalists and anticapitalists clashed in the streets.
DO    The email address for the webmaster can be found on the website.
With prefixes before a proper name, number or date
DO    anti-Thatcherism
DO    pre-2000 politics
DO    Hilary term starts in mid-January.
In numbers which are spelt out (though see ‘Numbers’ above for advice on this)
DO    Twenty-seven is the most popular ‘random’ number.
DO    The Thirty-Nine Steps
In compass points (unless used geographically rather than as directions)
DO    They’re heading south-east.
DO    nor’-nor’-east
DO    The southwest is a popular holiday destination.
 

When not to use a hyphen

In noun phrases

DO    Labour Party conference
DO    The 19th century saw much reform.

To make a new compound noun – if it is a recognisable concept, make it one word; if it isn’t, use two words

DO    Websites are made up of webpages.
DO    Send me an email when you’re ready to proceed.
DON’T    Send me an e-mail.

In an adjectival phrase that does not precede a noun

DO    Anyone can study part time at the Department for Continuing Education.
DO    The list was up to date.
DO    His marks just scraped into the first class.

In an adjectival phrase before a noun where the first element is an adverb ending in -ly (but note that any other adverbs in adjectival phrases do take a hyphen)

DO    She had a finely tuned ear for off-key music.
DO    XML documents must be well-formed texts.
DON’T    She was a highly-respected tutor.
DO    She was a badly paid apprentice.
 

Ellipsis…

Use an ellipsis to show that some text is missing, usually from a quotation. Do not surround it with spaces.
DO    …we shall fight on the beaches…we shall never surrender…
DO    It is a truth universally acknowledged…

There is no need to add square brackets around an ellipsis.

DON’T    […]we shall fight on the beaches[…]

Use an ellipsis to indicate a pause for comic or other effect – follow the ellipsis with a space in this case, as it stands in place of a comma or full stop.

DO    We need to change attitudes… and change them we will.

Note that, if used either in place of omitted text at the end of a clause/sentence or to indicate a pause for effect, a full stop/comma should not follow the ellipsis. However, an exclamation mark or a question mark can and should follow the ellipsis if required.

DO    Are you…?
DO    Did he say that…?

Use an ellipsis to indicate a trailing off in speech or thought.

DO    We could do this…or maybe that…

Full stop, exclamation mark and question mark

Use one – but only one – of these at the end of every sentence. 
DO    What time did you leave last night?
DO    We went home at 5 o’clock.
DO    Go home now!
 
Do not use a full stop at the end of titles, even if they make a sentence, but, if a title ends with an exclamation mark or question mark, do include it.

DO    All’s Well that Ends Well is my favourite play.
DO    ‘Will You Still Love Me Tomorrow?’ was a hit for the Shirelles.
DO    ‘Help!’ was covered by Bananarama in 1989.
DO    My favourite holiday destination is Westward Ho!

Do not use a full stop if it will be followed, or preceded, by an ellipsis.

DON’T    Behind him stood a figure. …It was ghostly grey.

Use a full stop, not a question mark, at the end of a reported question – only use a question mark for a direct question (whether in quotation marks or not).
DO    He asked if I wanted to go home that morning.
DO    ‘Do you want to go home this morning?’ he asked.
DON’T    He asked if I wanted to go home?

Use a full stop, not an exclamation mark, at the end of a reported imperative.

DO    Wait for me!  →    He asked me to wait for him.

Quotation marks

Use single quotation marks for direct speech or a quote, and double quotation marks for direct speech or a quote within that.

DO    ‘I have never been to Norway,’ he said, ‘but I have heard it described as “the Wales of the North”.’

Use no quotation marks if the quote is displayed (ie not in line with the rest of the text).

DO    as I noted then,
    Those of us who toil in the Groves of Academe 
know full well that our research helps inform 
our teaching…

Use single quotation marks and roman (not italic) type for titles that are not whole publications: eg short poems, short stories, songs, chapters in books, articles in periodicals etc. See also Highlighting/emphasising text.

DO    I, Robot contains nine short stories, of which ‘Little Lost Robot’ is my favourite.
DO    Queen’s ‘Bohemian Rhapsody’, from the album Night at the Opera, reached number one in both 1975 and 1991.

Using other punctuation with quotation marks

If the quote would have required punctuation in its original form, place the punctuation inside the quotation marks. (If it is unclear, try writing the whole sentence out without quotation marks and ‘he said’ etc, and replicate the resulting punctuation.)

DO    Bob likes cheese.  →  ‘Bob’, I said, ‘likes cheese.’    OR
‘Bob likes cheese,’ I said.

DO    Bob, do you like cheese?  →  ‘Bob,’ I asked, ‘do you like cheese?’
DO    Out, damn’d spot!  →  ‘Out,’ said Lady Macbeth, ‘damn’d spot!’
DO    ‘You’re engaged to Florence?’ I yipped, looking at him with a wild surmise.
 
Place any punctuation which does not belong to the quote outside the quotation marks (except closing punctuation if the end of the quote is also the end of the sentence).

DO    After all, tomorrow is another day.  →  ‘After all,’ said Scarlett, ‘tomorrow is another day.’  OR
‘After all, tomorrow’, said Scarlett, ‘is another day.’
DON’T    ‘The kitchen,’ he said, ‘is the heart of the home’.
DO    ‘The kitchen’, he said, ‘is the heart of the home.’

Note that American English has different rules about the use of quotation marks.