Punctuation

Don’t use the archaic form for plurals.

For plural nouns that don’t already end in s, add an apostrophe and an s (’s) to the end of the word. For nouns (singular or plural) that already end in s, add an apostrophe. Here are some examples:

  • Arkansas’ legislature
  • The witness’ testimony
  • Many businesses’ services

The exception is if it’s a book title or proper noun which uses the archaic form:

  • Lord Williams’s School

Colons

A colon indicates that closely-related information follows.

In a sentence, capitalise the first word after the colon if what follows the colon could function alone as a complete sentence. Use a single space following the colon. Place colons outside quotation marks when used together. Here are some examples:

  • This is it: the chance we’ve been waiting for!
  • This is it: We’ll never have to work again!
  • I feel sad when I hear the ending to “The Road Not Taken”: “And that has made all the difference.”

Do not use a colon at the end of a sentence to indicate a relationship with the following list or image. Instead, use the following with a full stop.

Commas

Use commas to separate items in series, and use commas to separate certain kinds of clauses.

In a series consisting of three or more elements, separate the elements with commas. When a conjunction (like, and, or or) joins the last two elements in a series, include a comma before the conjunction (the Oxford comma). Here are some examples:

  • He went to Dewey, Cheatem, and Howe for financial advice.

When using an ampersand in place of and in a series (acceptable only in company names and when space is severely limited, as in a headline), do not insert a comma before it. The combination of comma and ampersand creates visual clutter.

  • He went to Dewey, Cheatem & Howe for financial advice.

Dashes

When you need a dash, use an em dash.

Hyphen

A hyphen is used to mean to, up to and including, or through in a range of numbers, dates, game scores, pages, and so on. It is also used to construct a compound adjective that includes a proper noun of more than one word. (New York, Queen Elizabeth, Lake Baikal, and World War II are all multiword proper nouns.) If you are unsure whether a word combination should be two words, two hyphenated words, or one compound word, check the online Google Dictionary.

  • Abraham Lincoln (1809-1865) was president during the American Civil War (1861-1865).
  • Jim was interested in the pre-Civil War era. (En dash connecting two-word proper noun “Civil War” with prefix “pre-”)

En dash versus em dash

Prefer en dashes over em dashes, with a space either side.

Use an em dash to set apart entire phrases from the main body of a sentence, and separate the dashes from the words that precede and follow it with a space. When a date range has no ending date, use an em dash instead.

  • The last place she expected to find him — if she ever found him at all — was in the back seat of her car.

  • Mick Jagger (1943—), Brian Jones (1942-1969), and Keith Richards (1943—) were among the band’s original members.

Exclamation marks

Don’t use exclamation points in text except when they’re part of a code example.

Full stops

End a complete sentence with a full stop, unless it’s a question.

Do not put a full stop at the end of headings. See also bullet points, below.

Speech marks

Use straight double quotation marks.

Prefer double speech marks over single ones. Exception: when referencing a piece of data. e.g. The title field contains ‘Hobbit’.

Full stops go outside the speech marks when the text inside the speech marks is not a complete sentence.

  • Don’t use the phrase click here.

Bullet point and numbered list punctuation

  • Use a full stop after every bullet point that is a complete sentence.
  • Do not introduce bullet points with an incomplete sentence.
  • Use no punctuation after bullets that are not sentences or are very short e.g. Click Add.
  • Use all sentences or all fragments, not a mixture.
  • Do not use semi-colons at the end of bullets.