Small marks, big meaning
Punctuation changes meaning. Compare:
- Let’s eat, Grandma.
- Let’s eat Grandma.
Commas, apostrophes and quotation marks are three of the most frequently used, and misused, marks in English. Mastering them makes your writing clear and professional.
Part 1: Commas
A comma separates parts of a sentence and signals a brief pause. Here are the essential rules.
1. Items in a series
Use commas between three or more items.
We packed tents, sleeping bags, and flashlights.
The comma before and (the serial or Oxford comma) is optional in many Canadian styles, but be consistent. It can prevent confusion: I thanked my parents, Ana, and Leo (four people?) versus I thanked my parents, Ana and Leo (could suggest Ana and Leo are your parents).
2. Compound sentences
Use a comma before a coordinating conjunction (for, and, nor, but, or, yet, so) that joins two independent clauses.
The storm intensified, so the game was postponed.
Do not use a comma alone to join two independent clauses; that is a comma splice.
✗ The storm intensified, the game was postponed.
3. Introductory elements
Use a comma after an introductory element: a word, phrase or dependent clause before the main clause.
- However, the results were surprising.
- After the long hike, we collapsed into our tents.
- When the bell rang, students rushed out.
4. Nonessential elements
Use commas around a nonessential element: information that adds detail but could be removed without changing the core meaning.
My brother, who lives in Calgary, is visiting next week. (I have one brother; the location is extra.)
Compare with essential information (no commas):
Students who finish early may read silently. (Only those students; the clause is essential.)
Appositives follow the same rule: Ms. Kaur, our science teacher, organized the trip.
5. Direct address
Jordan, please close the window. / Thanks for your help, Mia.
6. Dates, addresses and numbers
- On July 1, 1867, Canada became a country.
- She moved to Halifax, Nova Scotia, last year.
- The stadium holds 45,000 people.
7. Coordinate adjectives
Use a comma between adjectives that equally describe a noun. Test: can you put and between them or switch their order?
It was a long, exhausting day. (long and exhausting ✓)
She wore a bright red coat. (no comma; bright describes red)
Part 2: Apostrophes
An apostrophe has two main jobs.
1. Possession
The possessive form shows ownership.
| Situation | Rule | Example |
|---|---|---|
| Singular noun | add ‘s | the dog’s bowl, James’s book |
| Plural noun ending in s | add ‘ only | the dogs’ bowls, the students’ lockers |
| Plural noun not ending in s | add ‘s | the children’s toys, the women’s team |
| Joint ownership | ‘s on the last name | Sam and Lee’s project |
| Individual ownership | ‘s on each name | Sam’s and Lee’s projects |
2. Contractions
The apostrophe replaces missing letters: do not → don’t, it is → it’s, they are → they’re, I would → I’d.
Never for plurals
✗ Apple’s for sale. ✓ Apples for sale.
✗ The 1990’s. ✓ The 1990s.
It’s vs. its
- it’s = it is / it has: It’s raining.
- its = possessive (no apostrophe): The bird built its nest.
Same pattern: your/you’re, their/they’re, whose/who’s. Possessive pronouns never take apostrophes.
Part 3: Quotation marks
Direct quotations
Use quotation marks around a direct quotation: someone’s exact words.
“I’ll be there at noon,” said Ravi.
Ravi said, “I’ll be there at noon.”
“I’ll be there,” said Ravi, “but I might be late.”
Do not use quotation marks for indirect speech: Ravi said that he would be there at noon.
Punctuation placement (Canadian/American style)
- Commas and periods go inside the closing quotation mark: “Let’s go,” she said.
- Question marks and exclamation marks go inside if they belong to the quotation, outside if they belong to the whole sentence:
- She asked, “Are you ready?”
- Did he really say “no homework”?
- Colons and semicolons go outside.
Dialogue formatting
Start a new paragraph each time the speaker changes.
Titles of short works
Use quotation marks for titles of short works: short stories, poems, songs, articles, episodes. Use italics (or underlining when handwriting) for long works: novels, films, magazines, albums.
“The Road Not Taken” appears in a collection of Robert Frost’s poems.
Quotations within quotations
Use single quotation marks inside double ones: “Did she say ‘see you tomorrow’?” asked Lin.
Common mistakes
- Comma splices.
- Missing comma after a long introductory element.
- Commas around essential information.
- Apostrophes in plurals and in possessive pronouns.
- Punctuation outside quotation marks where it belongs inside.
- Forgetting a new paragraph for a new speaker.
Try it yourself
- Add commas: Although it was raining the team which had trained for months played anyway.
- Fix: The girls locker room was being painted so it’s door was closed.
- Punctuate: Where are you going asked Mom
- Comma or no comma? The student (,) who scored highest (,) will win a prize.
Answers: 1. Although it was raining, the team, which had trained for months, played anyway. 2. The girls’ locker room was being painted, so its door was closed. 3. “Where are you going?” asked Mom. 4. No commas; the clause is essential.
Study tip
When editing, scan for one mark at a time: first all commas, then apostrophes, then quotation marks. Focusing on one rule per pass catches far more errors.
Quick recap
- Commas separate series items, join compound sentences with conjunctions, follow introductory elements and surround nonessential information.
- Apostrophes show possession and form contractions, never plurals.
- Quotation marks enclose exact words and short-work titles.
- Commas and periods go inside closing quotation marks.
- Start a new paragraph for each new speaker.