Do you write “her husband Bob” or “her husband, Bob“? Does the question mark — or comma or semicolon or colon — go inside or outside of the quotation marks? How do you use semicolons for lists? And where do we stand on the Oxford comma anyway?

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Colon

  1. Use a colon to introduce more information, including an example or list, including a bulleted list.
    • Example: The conference has three themes: global warming, climate control and energy alternatives.
  2. Colons also introduce examples, illustrative details and formal questions, taking the place of for example, namely or that is.
    • Example: There’s only one solution to your problem: a new job.
  3. Generally, don’t capitalize the first letter of a sentence that follows a colon, but it can be capitalized when the sentence is long or needs emphasis.
    • Example: Note: Colons go outside quotation marks.

Semicolon

  1. Sentences may be linked by a semicolon when they are closely related.
    • Example: The man tripped over the footstool; he’d been drinking.
  2. Although closely related, these are both complete sentences. If the second sentence can’t stand on its own, use a colon, a dash or a comma.
    • Incorrect vs. Correct Examples:
    • Both worked for the University of Guelph; he as a research scientist and she as a biologist.
    • Both worked for the University of Guelph; he was a research scientist and she was a biologist.
  3. Use semicolons to separate phrases if any of the phrases contain a comma. Note the last semicolon before and.
    • Example: The speakers were U of T biologist John Smith; Harry Jones, head of psychiatry at Michigan State University; Queen’s University philosopher Marian Wilkes; and University of Guelph sociologist Belinda Leach.
  4. Use semicolons at ends of lines in a bulleted list. Include “and” after the final semicolon. Add a period after the final bullet point. (For short bullet entries, you may omit punctuation.)
    • Example: Many other applications have been developed at U of G, including:
      • a hand-held device to measure metabolic disease indicators;
      • mathematical programs that model economic consequences; and
      • an automated wireless sensor network.

Note: Semicolons go outside quotation marks.

Comma

The Oxford comma: When writing lists of three or more items, some publications use an Oxford comma (also called a serial comma) before the last item in the list: She has a BA, an MA, and a PhD.

  1. We do not use a comma before “and“, “or” or “nor” in a list unless needed for clarity.
    • Example: She has a BA, an MA and a PhD.
  2. Use a comma when the final item in a list includes more than one element separated by “and”. In the below example “Fish and chips” is considered a single element of a three-item list.
    • Example: The menu includes hamburgers, pizza, and fish and chips.
  3. Or if fish is one item and chips is a another item on a four-item list (no Oxford comma).
    • Example: The menu includes hamburgers, pizza, fish and chips.

Dates

  1. Put commas between the day of the month and the year, and after the year. Incorrect vs. correct examples below:
    • Aug. 20, 2011 is the last day to enrol.
    • Aug. 20, 2011, is the last day to enrol.
  2. If a weekday is mentioned, it also takes a comma:
    • Example: Saturday, Aug. 20, 2011, is the last day to enrol.
  3. There’s no comma when the day of the month isn’t used:
    • Example: August 2011.

Places

Put commas between a city and its province or country, and after the province or country.

  • He was born in Wiarton, Ont. and moved to London, England at age five.
  • He was born in Wiarton, Ont., and moved to London, England, at age five.

Email Addresses

  • Send email to Lori Bona Hunt, lhunt@uoguelph.ca or call Ext. 53338.
  • Send email to Lori Bona Hunt, lhunt@uoguelph.ca, or call Ext. 53338.

Telephone Numbers

  • Call 519-824-4120, Ext. 56580 to be placed on the guest list.
  • Call 519-824-4120, Ext. 56580, to be placed on the guest list.

Numbers

Use a comma to separate thousands, hundred-thousands, millions, etc.

  • The event drew 1200 people.
  • The event drew 1,200 people.

Professional Titles

When putting a person’s title in front of his or her name, the form of the title will determine whether commas are required.

NO COMMAS: President Charlotte Yates and Linamar CEO Linda Hasenfratz announced the creation of the Linamar Engineering Design Scholarships.

COMMAS NEEDED: The president of the University of Guelph, Charlotte Yates, and Linamar’s CEO, Linda Hasenfratz, announced the creation of the Linamar Engineering Design Scholarships.

  • CSA president and former astronaut, Steve MacLean, says the top 16 candidates represent a well-rounded and diverse group of Canadians.
  • CSA president and former astronaut Steve MacLean says the top 16 candidates represent a well-rounded and diverse group of Canadians.
  • He will join the Office of Research as director, Animal Care Services April 1.
  • He will join the Office of Research as director, Animal Care Services, April 1.

Miscellaneous Comma Issues

  1. The word too should normally be preceded and, in some cases, followed by a comma:
    • He is a doctor, too.
    • He, too, is a doctor.
  2. Use a comma before such as when the words that follow aren’t essential to the meaning of the sentence. The meaning would be clear without mention of the Beatles and the Dave Clark Five.
    • Example: I am a fan of English rock bands from the 1960s, such as the Beatles and the Dave Clark Five.
  3. Don’t use a comma before such as when what follows defines or limits what went before. In this case, Iron Maiden is essential to explain what kind of bands he doesn’t like.
    • Example: He doesn’t like bands such as Iron Maiden.
  4. Use a comma before including when the words that follow aren’t essential to the meaning of the sentence:
    • Example: The talks will focus on a range of environmental topics, including climate change and water conservation.
  5. Do not put a comma after including:
    • Example: The talks will focus on a range of environmental topics, including, climate change and water conservation.
  6. Use of a comma with the word so also depends on whether or not the words that follow are essential to the sentence’s meaning. Here are two sentences that are the same except for a comma, and the comma totally changes the meaning. The first sentence says the office is closing early specifically so I can get to the bank before it closes. The so clause is necessary to explain that meaning, so there is no comma. The second sentence says the office is closing early and, because of that, I can get to the bank before it closes. This so clause is independent and requires a comma. See examples below:
    • The office is closing at 4 p.m. today so I can get to the bank before it closes.
    • The office is closing at 4 p.m. today, so I can get to the bank before it closes.
  7. Use commas to indicate omission. In the following sentences, the word omitted is that:
    • Example: The problem is, we don’t know how to get the word out to students.
  8. In the following sentence, the words omitted are was elected. Note the semicolons in this example; it’s needed because the second and third phrases contain commas.
    • Example: Smith was elected president; Williams, vice-president; and Armstrong, treasurer.

Note: Commas (and periods) always go inside quotation marks, even if the quotation marks are around a single word.

Relative Clauses

Relative clauses that are essential to the meaning of a sentence do not take commas. Relative clauses that are not essential and merely add information are set off with commas.

  1. That and which:
    • That starts a clause that is essential to the noun it defines or narrows the topic, and no comma is used.
    • Which starts a clause that is not essential, and a comma is always required.
      • Essential clause: The Wednesday class that Prof. James Kirk teaches is cancelled this week.
      • Non-essential clause: Prof. James Kirk’s Wednesday class, which I never miss, is cancelled this week.
    • Essential clause example:
      • The study is the first to examine the effects of saturated fat and caffeinated coffee on blood-sugar levels using a novel fat cocktail which contains only lipids.
      • The study is the first to examine the effects of saturated fat and caffeinated coffee on blood-sugar levels using a novel fat cocktail that contains only lipids.
    • Non-essential clause example:
      • The most visible evidence of the one-health approach is the $70-million Pathobiology/AHL building that supports the growing role of veterinarians and scientists in research and educational initiatives related to public health.
      • The most visible evidence of the one-health approach is the $70-million Pathobiology/AHL building, which supports the growing role of veterinarians and scientists in research and educational initiatives related to public health.
  2. Where can start both essential and non-essential clauses, so use of commas will vary.
    • Essential clause: After years of travelling the world, the tenor returned to Canada last month to perform at the school where his singing career began.
    • Non-essential clause: After years of travelling the world, the tenor returned to Canada last month to perform at the Randolph Academy for the Performing Arts, where his singing career began.
    • After her education in Jamaica, she went to England where she completed a PhD.
    • After her education in Jamaica, she went to England, where she completed a PhD.
  3. Who/whom and whose also start both essential and non-essential clauses.
    • Essential clause: My friend who lives in California is coming to visit next week.
    • Non-essential clause: My mother, who lives in California, is coming to visit next week.
    • Essential clause: The co-worker whose car I borrowed wasn’t happy that I got a ticket.
    • Non-essential clause: My brother Dick, whose car I borrowed, wasn’t happy that I got a ticket.
    • The Gryphon men were led by Kyle Boorsma who won gold medals in the 1,300m and 1,500m.
    • The Gryphon men were led by Kyle Boorsma, who won gold medals in the 1,300m and 1,500m.

Words in apposition

Apposition is a construction in which a noun or noun phrase is placed with another as an explanatory equivalent. When the explanatory phrase is not crucial to the meaning of a sentence, it is set off with commas. If it is crucial, don’t use commas.

  1. Here is an example where the words in apposition weren’t crucial to the sentence’s meaning, so commas should have been used.
    • She launched her debut album The Small Things in November.
    • She launched her debut album, The Small Things, in November.
  2. Here is an example where the words in apposition are vital to the meaning of the sentence and should not have been set off with commas.
    • The series begins with the critically acclaimed film, The Hurt Locker, at 7 p.m.
    • The series begins with the critically acclaimed film The Hurt Locker at 7 p.m.
  3. Some of the most common mistakes in punctuating words in apposition involve relationships.
    • Example: Suppose Mary is married to Larry, and they have three daughters.
      • Mary’s husband, Larry, is a farmer. Commas are needed because he’s her only husband, so his name isn’t necessary to the meaning of the sentence.
      • Her daughter Amy lives in Toronto. Mary has three daughters, so commas would be wrong in this case. Amy’s name needs to be there to identify which daughter.
      • Mary’s youngest daughter, Katie, is living in New Zealand. Commas are used here because the name Katie isn’t necessary to identify the daughter discussed.

Note: When interviewing someone who talks about a daughter, a brother, a dog, etc., ask the person if that’s the only daughter, brother or dog he or she has. That will determine whether commas are needed when mentioning the name of the daughter, brother or dog.

Compound Sentences

  1. A compound sentence with two independent clauses joined by a coordinating conjunction (and, but, for, or, nor, so, yet) should normally have a comma before the conjunction to avoid confusion.
    • Classes have been cancelled for the rest of the day, and the University has decided to send all employees home.
    • The weather doesn’t look promising, but the team is heading for Florida anyway.
  2. If two clauses joined by and are short, sometimes the comma can be omitted, but if there’s any chance of confusion, keep it in.
    • Susan shot the intruder and her brother hid. (A comma after and would keep the reader from momentarily thinking that Susan shot her brother.)
  3. When the second of two independent clauses does not have a subject in front of the verb, don’t use a comma.
    • The University has cancelled classes for the rest of the day and has decided to send all employees home.
    • The team is heading for Florida but will turn back if the weather is bad.

Consecutive Adjectives

Commas are not always necessary between consecutive adjectives. Adjectives that refer to age, size, colour or location are generally not set off with commas when combined with other adjectives. To determine whether there should be a comma between adjectives, mentally place an and between the adjectives or switch their order. If doing that makes it sound awkward or wrong, there shouldn’t be a comma.

  • The pretty red dress (The pretty and red dress and the red pretty dress both sound wrong, so there should be no comma.)
  • harsh, Arctic environment; wide, oak desk; small, niche market

Introductory Phrases

Introductory phrases should generally be set off with a comma, although short ones and single words (in recent months, on Saturday, suddenly, etc.) can go without a comma if the meaning is clear.

  • A team led by Guelph researchers discovered that for some male birds travelling to areas with lighter rainfall comes at the cost of attracting a female when they return home.
  • A team led by Guelph researchers discovered that for some male birds, travelling to areas with lighter rainfall comes at the cost of attracting a female when they return home.

Period

Rely on periods and strong writing instead of sprinkling exclamation points in efforts to generate excitement. You may use exclamation points in promotional materials! But if everything is exciting, then nothing is! You see the point!

Remember to add a period after a URL at the end of a sentence

Quotation Marks

  1. Use double quotation marks around dialogue or quoted sentences, phrases and words. Single quotation marks enclose quotations within quotations.
    • Example: John said, Tell me again about your ‘earth-shattering moment’ today.
  2. Use double quotation marks around words used as irony, slang or jargon.
    • Example: The giant snake in the UC turned out to be a baby ball python.
  3. Place a period or comma inside a closing quotation mark, not outside. In dialogue, the quotation mark always goes outside the final punctuation.
    • Example: He said, Bring the mace to the convocation ceremony.

Note:

  • Place titles of research papers inside quotation marks.
  • Use single, not double, quotation marks in headlines.

Apostrophes

Its is a possessive pronoun; it’s is the contraction of it is.

Singular Nouns and Names

Singular nouns and names ending in s, ss or an s sound form the possessive by adding an apostrophe and s.

  • Examples: the boss’s office, Marcus’s computer, Fritz’s pen.

Plural Nouns and Names

  1. Plural nouns and names take only an apostrophe.
    • Examples: the teachers’ meeting, the universities’ deficits, the Joneses’ house.
  2. Names ending in a silent s or x take an apostrophe and s.
    • Examples: Duplessis’s cabinet, Malraux’s paintings.
  3. Where the usage is more descriptive than possessive, omit the apostrophe.
    • Examples: the Board of Governors meeting, the Gryphons coach.

Letters

  1. Use an apostrophe and an s to form plurals with small letters (p’s and q’s).
  2. With capital letters, don’t use an apostrophe (the three Rs) unless the reader would be confused (write I’s and U’s to avoid appearing as Is and Us).
  3. Omit apostrophes in capped abbreviations (PhDs, UFOs) and numbers (1970s, 747s).

Amounts of Time

When referring to lengths of time, if someone worked at the University of Guelph for 25 years, she has 25 years’ service or 25 years of service, NOT 25 years service. But someone is three months pregnant, not three months’ pregnant.

Ownership

  1. If ownership is joint, the last noun is possessive and takes an apostrophe.
    • Example: Mary and Larry’s farm.
  2. If ownership is separate, each noun takes an apostrophe.
    • Example: Mary’s and Lori’s offices.

Organizations

When writing the name of an organization such as the Writers’ Trust of Canada or the Ontario Coloured Bean Growers Association, check the organization’s official website and follow its style. Write farmers market, not farmers’ market or farmer’s market. Farmers here is descriptive, not possessive.

Hyphens

Compound Adjectives

  1. Compound adjectives are often hyphenated before the noun they modify.
    • Example: eight-member team, $5-million project, first-year student, post-secondary education.
  2. But you don’t need to hyphenate if the meaning is instantly clear because of common use.
    • Example: high school teacher.
  3. Hyphenate words to avoid ambiguity.
    • Example: large-animal veterinarian.
  4. Use hyphens with successive compound adjectives.
    • Example: 18th- and 19th-century fashions.
  5. Most well-known compounds of three or more words are hyphenated.
    • Example: two-year-old.

Amounts

When numbers are quantifiers, not modifiers, no hyphen is needed.

  • One-million litres of milk, 35-million people.

Adverbs

Adverbs ending in ly are generally not followed by a hyphen because the ly eliminates ambiguity.

  • Highly-skilled actor, newly-created committee, genetically-modified food.

Prefixes

In general, use a hyphen to avoid duplicating two vowels in words with a prefix: pre-eminent, anti-inflammatory.

Not all cases are hyphenated. Refer to the Canadian Press Caps and Spelling for proper hyphenation of words with prefixes. If a word is not listed in Caps and Spelling, refer to the Canadian Oxford Dictionary.