Punctuation—Where, When, Why, and How to Use It

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P is for Punctuation
Where, When, Why, and How to Use It

Punctuation. Where, when, why, and how to use it. Apostrophe, colon, comma, em dash, en dash, ellipsis, hyphen, period, question mark, exclamation mark, parentheses, quotation mark, semicolon.

Did you know some punctuation “rules” are really only style choices? There are different styles of punctuation depending on what you are writing (e.g., manuscript, news story, legal document). The variations are minor but can be significant, especially to your editor. The punctuation guidelines listed here are geared toward novel-length fiction and non-fiction writing based on The Chicago Manual of Style.

Each type of punctuation has “rules” about what it does, where you should use it, when you should use it, why you should use it, and how to use it correctly.

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Apostrophe | Colon | Comma | Ellipsis | Em dash | En dash | Exclamation point
Hyphen | Parentheses | Period | Question mark | Quotation marks | Semicolon

If you don’t want to deal with all the rules, there is another acceptable option. Please note this option doesn’t conform strictly to The Chicago Manual of Style, but it isn’t technically incorrect.

If the singular noun (before being possessive) ends in “s,” then only add an apostrophe; otherwise, add “‘s.” If the noun is plural, you never add the “s.”

Note: For words and numbers that begin with an apostrophe, if you are using “smart quotes,” the bottom of the quote should curl forward. Sometimes, with modern word processors, it is necessary to type a placeholder letter, then the apostrophe, then the desired number or letter to generate the correct symbol, and delete the placeholder letter.

1. Contractions

Example: It’s (it is), can’t (cannot), don’t (do not), won’t (will not), he’d (he would or he had)

2. Omitted numbers

Example: The class of ’77

3. Omitted letters (particularly slang)

Example: If it doesn’t kill ’em, it won’t hurt ’em.

4 To pluralize letters and words

Example 1: Are you enjoying the do’s and don’t’s of punctuation?
Example 2: Beth had 4 A’s and 2 B’s on her report card.

5. To show possession (The rules below are in accordance with The Chicago Manual of Style. The acceptable alternative (with some editors) was given above.)

5A. Nouns (singular): to show possession, add “‘s”

Example 1: Robert’s book
Example 2: My mom and dad’s car. (Only the last element of a noun unit takes the possessive case)

Exceptions (when to leave off the final “s”)

1. When the singular form of a noun ending in “s” looks like a plural and the plural form is the same as the singular, the possessive of both singular and plural is formed by the apostrophe only.
2. Add an apostrophe only when the last element of a name is a plural form ending in “s.”
3. Leave off the final “s” with names of two or more syllables that end in an “eez” sound (e.g. Euripedes).
4. Leave off the final “s” with names or words that end in a silent “s” (e.g., marquis).

5B. Nouns (plural): to show possession, add only an apostrophe (no “s”)

Example 1: The cows’ pasture. (multiple cows)
Example 2: The babies’ blankets. (multiple babies, multiple blankets)
Example 3: The Smiths’ home (The home of all the Smith family members)

6. Double possessives

Example 1: This is a portrait of Angela’s (Angela owns more than one portrait.)
Example 2: Melinda is a friend of Mark’s (Mark has more than one friend, and one friend is named Melinda.)

7. Idiomatic expressions/Genitive case

Example: For goodness’ sake, two weeks’ notice, a week’s worth, five days’ leave, hard day’s work

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The colon is used after an introductory statement when the following statement explains, reaffirms, elaborates, elucidates, illustrates, or summarizes the preceding statement. Everything that follows a colon should be directly related to the topic in the introductory clause. The first word following a colon, even if it is the beginning of a complete sentence, should not be capitalized unless it is a proper noun. For stylistic reasons, it might be capitalized, but only do so for a good and defensible reason (especially to your editor). There is no space before a colon. You may find either one or two spaces after a colon. As with spacing after a period, it is becoming more common to see only one space after a colon.

1. Time

Example: 9:30 a.m.

2. Business salutation

Example: Dear Sir or Madam:

3. Headings

Example: Truck for sale: Dark blue, automatic, short box.

4. Title: subtitle

Example: Hiking in Glacier National Park: A Guide for Beginning to Advanced Hikers

5. Introduction of a series or list

Example: Beth painted her bedroom three colors: purple, pink, and blue.

5A. Don’t use a colon if one or more of the items in the list are needed to complete the introductory statement.

5B. Use a colon after the terms “as follows” and “the following”

5C. Don’t use a colon if a list is introduced with a phrase such as “such as”

6. A colon points the way to a revelation (the colon adds emphasis to the final clause)

Example: Beth put on her gloves, slid the envelope of pictures in her purse, and picked up the rope: it was time to complete her revenge.

7. A colon points to an explanation. (Answers the question “why?”)

Example: Billy stared at the wall: he couldn’t look her in the eyes after what he had done.

7A. Answers the question “what?”

Example: I have a secret: I robbed the bank.

8. A colon can point to an elaboration

Example: He was cautious with the people he made business deals with: he hired a private investigator to look into their backgrounds before agreeing to anything.

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1. In a series. This is the serial comma (a.k.a. the Oxford comma) and precedes the conjunction in a list of three or more items.

Example: Jennifer had vegetable soup, a turkey sandwich, and onion rings for lunch.

2. Dates. When the format of month, day, and year is used, a comma comes after the day (April 20, 2016).

3. Addresses. A comma is used between the city and the state (Boston, Massachusetts)

4. Degrees or titles used with names (Exception: commas are not used around Jr. or Sr.)

Example: David Smith, M.D., was the attending physician.

5. Direct address (a.k.a. vocatives)

Example 1: Put the book down, Nancy.
Example 2: Jim, what are you doing?
Example 3: Sit down, Brandon, and have a drink.

6. After introductory words and phrases or dependent clauses (Exception 1: When the introductory phrase is three words or less, the comma may be omitted if the omission does not create confusion. Exception 2: When the adverb or adverbial phrase modifies the whole sentence rather than a specific element of the sentence, a comma is needed.)

Example 1: After it stops raining, I’ll take the dog for a walk.
Example 2. Sadly, the woman didn’t survive the accident.
Example 3: Yes, I will help you.
Example 4: Reaching for her phone, she realized she left it in the car.

7. To set off nonessential (or nonrestrictive) elements

Example: The boys, not the girls, ate all the cookies.

8. Between independent clauses (complete sentences) joined by a coordinating conjunction (for, and, nor, but, or, yet, so)

Example: Katerina wanted to go to the party, but she had nothing to wear.

9. Appositives: if the words that follow a noun and describe it are nonrestrictive, set them off with commas

Example 1: Kimberly Johnson, lover of animals, volunteers at the animal shelter.
Example 2A: Cassidy’s brother, Thomas, hasn’t been home in years. (Cassidy has only one brother.)
Example 2B: Cassidy’s brother Thomas hasn’t been home in years. (Cassidy has more than one brother, but the one named Thomas hasn’t been home in years.)
Example 3A: Ben’s sister, wearing green shorts, is running on the track. (Nonrestrictive. Ben’s sister just happens to be wearing green shorts.)
Example 3B: The woman wearing green shorts ran into me. (Restrictive. The woman is defined, or restricted, by her green shorts.)

10. Between coordinate adjectives (adjectives that equally modify the same word).

Test 1: If “and” can be placed between two adjectives and the order can be changed without modifying the meaning, separate them with a comma.
Test 2: When each adjective alone can modify the noun and still make sense, separate the adjectives with a comma.

11. Nonrestrictive phrases and/or clauses, also known as parenthetical elements, should be set off by commas.

Example: The baker, who was frosting a cake at the time, didn’t notice the young boy taking the cupcakes.

12. Asides and interrupters are set off by commas

Example 1: Johnny was, as you can imagine, terrified when he saw the growling wolf.
Example 2: Brittany will, of course, handle the arrangements.

13. To set off phrases that modify something other than the preceding word

Example: Jenny threw herself on the couch, sobbing uncontrollably.

12] Between coordinate adjectives: adjectives that equally modify the same word.
Test 1:: when the word “and” could be placed between two adjectives and the adjective order can be swapped without modifying the meaning,
separate them with a comma. (Note: the test is not whether or not it sounds awkward, but does it change the meaning.)
Test 2: if each adjective alone could modify the noun and still make sense, separate the adjectives with a comma.

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There are different ways to handle the ellipsis. Some of these are affected by using the insert symbol feature in a word processor. One common way to handle the ellipsis is with no spaces between the periods and a space on each side of the ellipsis when it is between words and no space between the ellipsis and a quotation mark.

Stylistically, ellipses are best used to give a thoughtful, contemplative feel to prose. They do not always have to be part of a quotation and can be used in narrative. While ellipses can serve a purpose, they should be used sparingly and not overused.

1. An ellipsis takes the place of omitted words in a quotation

Example: “She was talking about dresses, skirts, pants … until she turned blue in the face.”

2. To indicate a long thoughtful pause

Example: I wanted to call her … no, needed to call her.

3. Indicates trailing off (as opposed to an abrupt interruption)

Example: I couldn’t hike any farther. I just couldn’t do it anymore. Just couldn’t …

4. To indicate a continuation of time

Example: The timer counted down: ten, nine, eight …

5. To indicate pauses in conversation as if a “realization” is occurring

Example:”Why would he … would they?”

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Em dash
An em dash marks a change in though, an interruption, an aside, or an appositive. It is called an em dash because it it the same width as an “M.” There are no spaces before or after an em dash. A question mark or exclamation point (but not a period) can appear before an em dash where appropriate.

1. An em dash precedes a quote attribution.

Example: “Description begins in the writer’s imagination, but should finish in the reader’s.”
—Stephen King, On Writing: A Memoir of the Craft

2. An interrupted thought or unfinished sentence

Example: Cathy said, “Please stop. Don’t—”

3. An em dash can set off parenthetical material

Example: His dog ran—tail wagging furiously—to greet him at the door.

4. A break in thought continuity

Example: Two stone gargoyles—Cassie had never seen something so hideous—guarded the entrance.

5. An abrupt, startling, or emphasized appositive

Example: Marcus—blood dripping down his face—walked into the kitchen.

6. To add emphasis on the last item in a list (often a jump in continuity from the previous elements)

Example: Mary hasn’t seen Jordan since the day he walked out the door and left her with crushed dreams, unpaid bills, and no car—and a baby on the way.

7. An aside

Example: I cleaned my fourteen-year-old son’s room—what a nightmare!—only to have it look like a tornado swept through it two days later.

8. A divided quote (interrupted by something narrative rather than attributive)

Example: “I’m leaving”—she took the car keys off the counter—”whether you like it or not.” (She is performing the action while speaking, but her words are spoken continuously.)

8A. If the actual quote is interrupted, the em dash goes inside the quotes

Example: “Because—” Mary shrugged her shoulders “—I don’t know what else to do.” (Mary’s spoken words are paused during the action.)

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En dash
An en dash is the approximate size of the letter “N.” There is no space before or after it. An en dash should never be used as a substitute for an em dash.

1. Dates

Example: 1981–1984

2. As a replacement for “to” or “up to and including” (If from is used, the en dash can’t be used and to must be used. If between is used, and must be used.)

Example: Read pages 85–115 in your textbook tonight.

3. To indicate something ongoing

Example: Jason Jones (1970–) is living in Wyoming. (Indicates he was born in 1970 and is still living.)

4. En dash in place of a hyphen in a compound adjective when one or more of its elements is an open compound or when two or more of its elements are hyphenated compounds

Example: a quasi-public–quasi-judicial body

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Exclamation point
An exclamation point can be used to convey emotion. Exclamation points are more acceptable in dialogue than in narrative, but in either case, they shouldn’t be overused.

To indicate direct commands, loud noises, anger, shouting shock or surprise, anything with heightened intensity, and disgust or sarcasm.

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There are no spaces before or after a hyphen. Hyphens can be used to combine words, provide clarity, or split words.

1. To break a word at the end of the line (Always split between syllables.)

2. Numbers: hyphenate numbers twenty-one through ninety-nine

3. Fractions: hyphenate in noun, adjective, and adverb forms except when the second element is already hyphenated (Exception: when discussing the individual parts, do not hyphenate—We cut the pie into four quarters.)

4. Compound modifiers that modify a noun: two or more words that together express a single idea are hyphenated if they precede a noun (e.g., brown-eyed girl, much-needed rest).

Exceptions to Number 4

1. If the adverb in an adverb/adjective or participle compound ends in -ly don’t hyphenate.
2. Don’t hyphenate after very, most, least, more, less
3. If the compound modifier is universally known and understood and/or there is no possible confusion of misreading, don’t hyphenate (e.g., chocolate chip cookie).
4. Compound modifiers formed completely of capitalized words should not be hyphenated (e.g., African American child).

5. Compounds with specific terms (Reference: The Chicago Manual of Style)

ache: always closed (e.g., toothache)
all: adjectival phrases hyphenated before or after a noun; adverbial phrases open (e.g., all-out war, all along)
book: open unless in the dictionary (e.g., reference book, cookbook)
borne: normally closed but hyphenated after words ending in b and after words of three or more syllables (e.g., waterborne, mosquito-borne)
cross: noun, adjective, and adverb forms hyphenated, except some permanent compounds (e.g., cross-reference, crossbow)
e: hyphenate (e.g., e-book, e-mail)
elect: usually hyphenated unless the name of the office consists of two or more words. (e.g., president-elect)
ever: hyphenate before a noun, except some permanent compounds (e.g., ever-ready, everlasting)
ex: hyphenate (e.g., ex-boyfriend)
fold: closed unless formed with a hyphenated number (e.g., tenfold, twenty-five-fold)

6. Normally open compound nouns may sometimes be hyphenated for clarity if preceded by a modifying adjective

Example: house cat vs. gray house-cat (add hyphen to make clear gray is describing the cat not the house)
Example 2: wine cellar vs. underground wine-cellar

7. Hanging hyphen: when the second part of the hyphenated expression is omitted, the hyphen is retained

Example 1: five- to ten-minute intervals
Example 2: fifteen- and sixteen-year-old students
Example 3: both over- and underestimated costs

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Parentheses are generally not used in fiction writing. There is no comma before the opening parenthesis. If parentheses are located within a sentence, even if they enclose a complete sentence, do not capitalize the first enclosed word (unless it is a proper noun) or end it with a period inside the closing parenthesis.

1. Numbers or letters in a series (in running text)
Example: The answers are (1) dog, (2) cat, and (3) horse.

2. An aside, parenthetical element, or a digression
Example: She wasn’t ready for the test (neither was I), but a last-minute study session would help.

3. Explanatory information
Example: The cookies (the chocolate chip ones) are gone.

4. To indicate doubt. (?)
The name of the diner is Grumby’s (?), or maybe Grimby’s.

5. To indicate surprise. (!)
Mary had changed so much (!) that I almost didn’t recognize her.

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There is no space before a period and only one space after. In the past (the days of the old typewriters), two spaces were used after a period, but thanks to modern kerning, this is no longer necessary. With quotation marks, periods go inside the closing quotation mark.

1. To end a complete sentence

Example: The dog chased the squirrel.

2. Abbreviations (General rule: use periods with abbreviations that appear in lowercase, but don’t use periods with those in uppercase)

Example 1: Mr., Mrs., Dist. Atty., Dr.
Example 2: e.g., i.e., etc., a.ka., USA, NASA, CEO

3. To punctuate a fragment

Example: She stopped dead in her tracks. Frozen.

4. A rhetorical question (Style note: Depending on the feel and/or tone of the rhetorical question, either a period or a question mark can be appropriate.)

Example 1: What difference does it make.
Example 2: How many times do I have to tell you to put your dirty clothes in the hamper.

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Question mark
Use no spaces before a question mark and one space after. If a direct question is preceded by an introductory phrase or clause, the first word of the question may be capitalized. It doesn’t have to be, but this adds a formal feel to the sentence. A question mark should be placed inside quotation marks or parentheses only when the quoted or parenthetical matter is a question.

1. Direct questions

Example: Did he leave?

2. Questions embedded within a sentence

Example: How soon will he arrive? she wondered.

2A. but is not used in an indirect question

Example: She wondered how soon he would arrive.

3. A series of questions within the same sentence

Example: How is your sleep affected by stress? drinking caffeine? drinking alcohol?

4. Can be used to turn a declarative statement into a question

Example 1: You don’t mind if I borrow your red sweater?
Example 2: You’re not excited?

5. Rhetorical questions: the question mark is optional

Example 1: What difference does it make. (Rhetorical and pessimistic)
Example 2: What difference does it make! (Rhetorical and possibly argumentative)
Example 3: What difference does it make? (More interrogative than rhetorical)

6. If a command is phrased, for politeness, as a question but is still essentially a command, no question mark is used

Example: Will you please put your dirty dishes in the sink. (As spoken by a parent to their child)

6A. But if it’s really a question, then use a question mark.

Example:Will you please put your dirty dishes in the sink? (When spoken as an earnest question)

7. A question mark can be used to create a feeling of stream of consciousness (stylistic usage)

Example: Was your trip everything you hoped? Did you meet any interesting people? learn something new? see anything you’ve never seen before?

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Quotation marks
Quotation marks are used most often with dialogue. They can be used for some other purposes, but this should be done sparingly. Quotation marks are not used to indicate thought. The exception would be when characters communicate telepathically, in which case a combination of italics (indicating the words are thought and not spoken) and quotation marks (indicating speech between characters) is used.

Commas and periods (when appropriate) are always placed inside the closing quotation mark. Question marks and exclamation marks go inside the closing quotation mark when they are part of the quoted material; however, they are placed outside of the closing quotation mark when they refer to the surrounding sentence rather than the material in quotes.

1. Direct quotations

Example 1: “I want cheesecake,” Sylva said.
Example 2: Sylva said, “I want cheesecake.”
Example 3: Can I have cheesecake?” Sylva asked.
Example 4: Sylva asked, “Can I have cheesecake?”
Example 5: “Oh my God, cheesecake!” Sylva screamed.
Example 6: Sylva screamed, “Oh my God, cheesecake!”
Example 7: “I think”—Sylva opened the box—”we should have cheesecake.” (Narrative interruption)
Example 8: “I think,” Sylva said, “we should have cheesecake.” (Attributive interruption)

2. To indicate irony

Example: His “medicine” made her sicker. (Exception: do not use quotes if preceded by “so-called” or “namely”)

3. To indicate a word used questionably or with meaning beyond the denotation

Example: Darlene arrived with her “friend.”

4. Can be used in place of italics to indicate word used as a word, instead of what it usually references (or a letter)

Example 1: The word “book” has four letters.
Example 2: Is there an “E” or an “I” in “bistro”?

1. When question marks and exclamation points refer to the surrounding sentence rather than the material in quotes, the question mark and exclamation point go outside the closing quotation mark.

Example: Are you attending the seminar titled “Punctuation—What, Where, When, Why, and How to Use It”?

2. Quotation marks aren’t used around indirect quotations.
Example: He said (that) he hated cheesecake.

3. Semicolons and colons, when adjacent to quotation marks, always go outside quotation marks.

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The semicolon should be used when the independent clauses (complete sentences) combine to convey a single thought. The semicolon balances two equally weighted elements. Some editors do not like semicolons in dialogue, but many published authors (and some editors) believe a semicolon is acceptable in dialogue; however, it shouldn’t be used in dialogue without good reason.

There are no spaces before a semicolon and a single space after it. The second independent clause (complete sentence) isn’t capitalized.

1. Semicolons can (and frequently should) be used in place of commas to clarify lists of items that contain internal commas

Example: At the party, I met George, the mayor; Margaret, the mayor’s cranky assistant; and Barbara, a published author.

2. Semicolons can be used between closely related independent clauses (complete sentences) that are not linked by a coordinating conjunction (for, and, nor, but, or, yet, so)

Example: Last year, he couldn’t get a job at a greasy spoon; today, he’s a gourmet chef.

3. A semicolon can be used to emphasize a contrast

Example: Winters were too cold; summers were too hot.

4. When a conjunctive adverb is used to transition between independent clauses (complete sentences), a semicolon introduces the conjunctive adverb

Example: Bobby thought he could use the rocks to cross the creek; however, when he tried, he fell in.

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I felt like I was back in English class! These were great refreshers, some rules I wasn’t even familar with!

Thank you for the refresher course. I am a casual writer and probably break these rules frequently. It must drive you crazy!

I was always told never to put a comma before the word ‘and’ so it’s interesting to learn that’s not always the case!

I think I need to go back to English class!! I have to! lol. This helped me to remember this important things

This topic can’t be communicated enough! It is crazy how many mistakes are made… (I don’t exclude myself here :))

Thank you for sharing! It is so useful. I thought i was good at punctuation but realise i get confused with semi-colons and don’t know the other uses for others x

After leaving school,I have never really payed attention to the way i write and all the grammar rules. But ever since I have started writing again, I feel like I need to go to the library to get back all those grammar rules books. So thanks for this post, it helped me a lot.