13.2 Punctuation and Capitalization

Punctuation Rules for Various Contexts

Punctuation marks do more than just end sentences. They control pacing, clarify meaning, and show relationships between ideas. Knowing which mark to use and when is what separates polished writing from confusing writing.

Using Commas, Semicolons, Colons, and Dashes

Commas are the most common punctuation mark, and the most misused. Here are the main situations where you need them:

• Series: Separate three or more items in a list (apples, bananas, and oranges).
• Introductory elements: After an introductory phrase or clause, drop in a comma before the main sentence (After the rain, the sun came out).
• Joining independent clauses: When you connect two complete sentences with a coordinating conjunction (for, and, nor, but, or, yet, so), place a comma before the conjunction (She sang beautifully, and the audience applauded).
• Nonrestrictive elements: Set off extra information that could be removed without changing the sentence's core meaning (My brother, who is a doctor, lives in New York).

Semicolons connect ideas that are closely related but could each stand alone as sentences:

• Between independent clauses without a conjunction: I have a big test tomorrow; I can't go out tonight.
• Between items in a series that already contain commas: The winners were John, from Chicago; Maria, from Los Angeles; and David, from Houston. Without semicolons here, the reader can't tell where one item ends and the next begins.

Colons signal that what follows explains, lists, or illustrates what came before:

• Introducing a list: I need three things: a pen, a notebook, and a calculator.
• Explaining a previous clause: She knew the answer: she had studied all night.
• Introducing a formal quotation: Shakespeare wrote: "To be, or not to be, that is the question."

Dashes (specifically em dashes) create a stronger pause than commas and signal interruption or emphasis:

• A sudden break in thought: I was going to the store—oh, I forgot my wallet.
• Setting off parenthetical elements with extra emphasis: The book—which was a bestseller—was made into a movie.
• Creating dramatic emphasis: She had only one thing on her mind—revenge.

Applying Rules for Quotation Marks, Parentheses, and Brackets

Quotation marks have three main uses:

• Direct quotations: Enclose the exact words someone said or wrote ("I love you," she said).
• Titles of short works: Use quotation marks for poems ("The Raven"), short stories ("The Necklace"), articles, songs, and individual episodes.
• Words used in a special sense: When referring to a word as a word itself (The word "love" has many meanings).

Single quotation marks appear only inside double quotation marks, for a quotation within a quotation: She said, "I heard him say, 'I quit.'"

Parentheses enclose supplemental information that adds context but isn't essential to the sentence:

• Dates: World War II (1939–1945)
• Clarifications: The study (see Figure 1) shows the results.
• Citations: The theory was first proposed by Einstein (1905).

Brackets are used inside quoted material to add editorial comments or corrections. They tell the reader that the bracketed words weren't part of the original quote:

• Clarification: "She [the teacher] gave us a test."
• Flagging an error in the original: "He said, 'I will return on Wedensday [sic].'" The word [sic] means the error was in the original text, not yours.

Mastering Punctuation Marks

Correctly Using Apostrophes and Hyphens

Apostrophes do two things: show possession and mark contractions.

• Possessives: For singular nouns, add 's (the cat's toy). For plural nouns already ending in s, add just an apostrophe (the girls' room).
• Contractions: The apostrophe replaces missing letters (can't, won't, it's).
• Common mistake: Never use apostrophes to form plurals. Write books, not book's. This error is so common it has a name: the grocer's apostrophe (because you see it on signs like "Apple's for sale").

Hyphens join words together to form a single idea:

• Use hyphens for compound modifiers that come before a noun: a well-known author, a part-time job.
• Don't hyphenate when the modifier comes after the noun: The author is well known.
• Don't hyphenate compound modifiers that start with an adverb ending in -ly: a beautifully written essay, not a beautifully-written essay. The -ly already signals that the adverb modifies the next word.

Proper Usage of Ellipses and Slashes

Ellipses (three spaced dots) indicate that something has been left out or that a thought trails off:

• Omitted words in a quotation: "We the People . . . do ordain and establish this Constitution."
• A pause or trailing thought in dialogue: "I was thinking . . . about the future."

Slashes have a few specific uses:

• Indicating a choice: and/or, pass/fail
• Separating lines of poetry quoted in running text: "Roses are red / Violets are blue"
• Expressing fractions: 3/4

Don't put spaces before or after a slash when separating words or numbers (write and/or, not and / or). When separating lines of poetry, a space on each side of the slash is standard.

Identifying Punctuation Errors

Recognizing and Fixing Comma Splices and Run-on Sentences

A comma splice happens when you use a comma alone to join two independent clauses (complete sentences). It's one of the most common errors in student writing.

• Comma splice: She studied hard, she passed the exam.

The problem is that a comma isn't strong enough to hold two independent clauses together by itself. You have four ways to fix it:

1. Period: She studied hard. She passed the exam.
2. Semicolon: She studied hard; she passed the exam.
3. Comma + coordinating conjunction: She studied hard, and she passed the exam.
4. Subordination: Because she studied hard, she passed the exam.

A run-on sentence (also called a fused sentence) is similar, but there's no punctuation at all between the independent clauses:

• Run-on: I love coffee I drink it every morning.

Fix it the same way: add a period, semicolon, or comma with a conjunction.

Avoiding Misuse and Incorrect Placement of Punctuation Marks

Some punctuation errors show up again and again. Here are the ones to watch for:

• Apostrophe errors: Don't write apple's when you mean the plural apples. Don't forget the apostrophe in contractions (don't, not dont).
• Quotation mark placement: In American English, commas and periods always go inside closing quotation marks: "What time is it?" she asked. "It's noon," he replied. Semicolons and colons go outside.
• Comma overuse: Adding commas wherever you'd pause in speech leads to cluttered writing. Every comma should have a grammatical reason.
• Comma underuse: Skipping the comma after an introductory clause or before a coordinating conjunction that joins two independent clauses can confuse readers.

Capitalization Rules in Writing

Capitalizing Proper Nouns and Titles

Proper nouns name specific people, places, organizations, and brands. They always get capitalized:

• People: John Smith
• Places: New York City
• Organizations: United Nations
• Brands: Apple

Titles of works (books, films, articles) follow specific capitalization rules. Capitalize:

• The first and last word, always
• All major words: nouns (The Great Gatsby), pronouns (Who's Afraid of Virginia Woolf?), verbs (Gone with the Wind), adjectives (The Scarlet Letter), and adverbs (Love Actually)

Do not capitalize minor words unless they're the first or last word of the title:

• Articles: a, an, the
• Short prepositions: of, in, to, for
• Coordinating conjunctions: and, but, or

So it's The Old Man and the Sea, with a lowercase "and" and "the" in the middle.

Applying Capitalization Rules in Various Contexts

• First word of a sentence: Always capitalized (The sun is shining).
• The pronoun "I": Always capitalized, no matter where it falls in a sentence.
• Days, months, and holidays: Capitalize Monday, January, Christmas.
• Seasons: Do not capitalize summer, winter, spring, or fall unless they're part of a proper noun (Winter Olympics, Spring Fling Dance).
• Family titles: Capitalize when used as a name or in place of a name (I saw Uncle John; Hey, Mom). Don't capitalize when preceded by a possessive like "my" or "her" (I saw my uncle; Tell your mom).
• Course names: Capitalize specific course titles (Biology 101, American Literature II). Don't capitalize general subject areas (She studies biology and history) unless the subject is a language (She studies English and French).