8. Confidently Place Commas

Originating from Greek and Latin texts, commas have evolved to become indispensable tools of clarity and precision. In modern writing, commas serve as signposts, creating rhythm and flow, highlighting pauses, separating ideas, and ensuring coherence.

Table 8.1 Use commas around nonessential (restrictive) words or phrases (click here)

Without Commas	Explanation	With Commas	Explanation
The painting by Picasso is worth millions.	This reference is restricted to a painting done by Picasso.	The painting, by Picasso, is worth millions.	This reference adds extra information about the painting but is not necessary for identification.
My son Wayne majored in economics.	The sentence indicates that you have more than one son. Wayne is necessary to identify which son you are referring to.	My son, Wayne, majored in economics.	If you have only one son, then his name is not necessary to understand the meaning of the sentence.
The street lined with trees marks the border between counties.	The phrase lined with trees identifies which street marks the border.	The street, lined with trees, is my favorite walking route.	Although descriptive, lined with trees is not essential to the meaning of the sentence.
All students who completed their assignments earned full credit.	The relative clause who completed their assignments identifies the students who received full credit.	Helga Karlsson, who married my cousin, teaches Introduction to Swedish.	In this sentence, the clause set off with commas, who married my cousin, is not necessary to complete the meaning of the sentence: Helga Karlsson teaches Swedish.
The book *that is alone on the shelf belongs to Samuel.	The relative clause that is alone on the shelf is essential to identify Samuel’s book.	The Poisonwood Bible, *which is Lisa’s favorite novel, was written by Barbara Kingsolver.	The clause set off with commas, which is Lisa’s favorite novel, is not necessary to complete the meaning of the sentence: The Poisonwood Bible was written by Barbara Kingsolver.

*The relative pronoun that is used with restrictive/essential clauses: information without which the reader might misunderstand the meaning of the sentence. The relative pronoun which is used with nonrestrictive/nonessential clauses: information not essential to the meaning of the sentence. The relative pronoun who may or may not have commas depending on the context, so the writer uses punctuation to indicate restriction.

The following video further clarifies the difference:

In summary, never use commas around a that clause. Always use commas around a which clause. Depending on its meaning, a who clause can go either way.

8.2 Use commas after introductory words, phrases, and clauses.

Commas prevent the intro act from stealing the show from the main act. Table 8.2 below highlights introductory words, phrases, and dependent clauses. Note that if the dependent clause comes after the independent clause, you should not use a comma.

Table 8.2 Use commas to set off introductory words, phrases, and clauses (click here)

8.3 Use commas to punctuate independent clauses joined by FANBOYS conjunctions.

Separate independent clauses that are joined by coordinating conjunctions—FANBOYS. The FANBOYS are for, and, nor, but, or, yet, and so.

Table 8.3.1 Use commas to separate independent clauses joined by FANBOYS conjunctions (click here)

If a sentence starts with a short independent clause—fewer than five words—the comma is optional: I will stay but she will go.

Table 8.3.2 Do not use commas between compounds (click here)

8.4 Use commas between items in a series—a list that contains three or more items. Use the Oxford comma before the last item in a series.

Use commas to separate all the items, including the last one.

In her speech, the sales VP thanked her team members, Shanna Parry and Miranda Parkinson.
In her speech, the sales VP thanked her team members, Shanna Parry, and Miranda Parkinson.
The first example does not clarify whether Shanna and Miranda are on the team. Using the Oxford comma to clarify meaning.

Many style guides (including Associated Press (AP), the most common journalistic style guide) do not require the Oxford comma. Chances are your school newspaper intentionally omits the Oxford comma. This textbook, however, follows Patricia O’Connor’s advice: “[The Oxford comma] doesn’t hurt and it creates clarity, so leave it in.”

Table 8.4 Use the Oxford comma before the last item in a series (click here)

8.5 Use commas to separate adjacent coordinate adjectives.

Place a comma between coordinate adjectives—two adjacent adjectives that equally modify a noun:

Table 8.5 Use commas to separate adjacent coordinate adjectives (click here)

To test whether you need a comma, insert the word and between the adjectives. If it makes sense, insert a comma between them.

8.6 Where to avoid commas

The previous rules showed you where to correctly place commas. This rule shows you places where you should never (well almost never) place commas. 

With few exceptions, avoid commas in the following situations: 

• Between a subject and its verb
• Between compound subjects, verbs, and objects (including correlative conjunctions)
• Between transitive verbs and their objects

For more information on comma-related errors, visit Purdue’s OWL.

9. Follow Three Rules for Using Semicolons

Semicolons have three specific uses: punctuating independent clauses not joined by FANBOYS conjunctions, separating series that contain internal commas, and punctuating independent clauses joined by conjunctive adverbs—words like therefore, however, nevertheless, moreover, and notwithstanding.

Table 9.1 Correctly use semicolons (click here)

Table 9.2 Do not use semicolons when words interrupt flow (click here)

*To be clear and concise, if you use i.e., which means in other words, consider eliminating everything to the left of the i.e. If you have to say in other words, you did not clearly, concisely express yourself in the first place.

Need a little more practice? Check out Grammar Girl's tips on semicolons.

10. **Use Colons Only After Complete Sentences

A colon introduces a list or series, example, quotation, or subtitle. It also separates time expressed in narrative writing.

Table 10 Correctly use colons (click here)

**In these two cases, the colon does not need to be preceded by an independent clause (a complete sentence).

For more information, read Grammar Girl’s advice on colons.

11. Differentiate Dashes from Hyphens

Dashes (—) are not hyphens (-).

Table 11.1 The hyphen (-) has three mechanical functions (click here)

For more help with hyphens, check out this site: How to Use a Hyphen.

12. Master Apostrophes and Quotation Marks

12.1 Apostrophes indicate contractions and possession.

Table 12.1.1 Apostrophes indicate contractions – missing letters (click here)

Table 12.1.2 Apostrophes indicate possession (click here)

***What do you do with names that end in -s, -es, -z, or -x? To keep things simple, this book adheres to the Chicago Manual of Style’s differentiation between references to one person versus a group.

For more on how to make names plural and possessive, read the Grammar Girl’s posts How to Make Family Names Plural and Apostrophe Catastrophes.

12.2 Use quotation marks to indicate someone is speaking, to enclose a direct quote from a secondary source, or to indicate titles of short works.

Table 12.2 Correctly use quotation marks (click here)

12.3 Correctly place punctuation marks inside or outside quotation marks.

Table 12.3 Correctly place punctuation marks relative to quotation marks (click here)

13. Capitalize Correctly

For the most part, capitalization rules apply across languages: capitalize the first word of every sentence and capitalize proper nouns. The difficulty arises when determining whether a noun is proper or common.

13.1 Capitalize specific proper nouns, but do not capitalize common nouns.

Explore the difference in Table 13.1 below.

Table 13.1 Capitalize specific proper nouns (click here)

13.2 Capitalize the first word of each item in a vertical list.

Make lists parallel, as emphasized in "Syntax and Word Choice." Note how each of these bullet items begins not only with an upper-case letter but also with a verb:

• Reduce days in receivables
• Hire a new IT manager
• Slash unnecessary expenses

13.3 Correctly capitalize titles and degrees

Table 13.3 Correctly capitalize book titles, job titles, and degrees (click here)

13.4 Capitalize the first word of direct quotations whose first word begins the sentence. Similarly, capitalize the first word of an internal question and a midsentence independent clause.

Table 13.4 Capitalizing quotations and internal questions (click here)

13.5 Capitalize compass points that refer to a specific place or region, not when they refer to a general area or direction.

Table 13.5 Capitalize specific compass points or regions (click here)

14. Know your numbers

The following basic rules are consistent with the Chicago Manual of Style, but you should consult your company’s style guide to learn the differences.

14.1 Generally, spell out single-digit numbers one through nine.

Use numerals for double-digit numbers 10 and higher, percentages, measurements, statistics, and page and chapter numbers. In sentences that contain numbers over and under 10, maintain consistency by using numerals.

Table 14.1 Correctly express numbers (click here)

14.2 Express large numbers—larger than one million—with a combination of decimals and verbal descriptors.

Table 14.2 Express numbers larger than one million with a combination of decimals & verbal descriptions (click here)

14.3 Express dates.

Generally, use the cardinal—1, 2, 3—number to express dates in writing. Ordinal numbers—1st, 2nd, 3rd—are allowable only if the date precedes the month. Although cardinal and ordinal forms are interchangeable in conversation, follow this rule in writing.

Table 14.3 Correctly express dates (click here)

14.5 Express fractions.

Express standalone fractions—numbers greater than zero but less than one—as hyphenated words. In business writing, replace fractions with percentages or decimals whenever possible.

Table 14.5 shows examples of how to express fractions and decimals, but you should follow your company's style guide.

Table 14.5 Express fractions as hyphenated words, percentages, or decimals (click here)

For more information on numbers, read the Business Writing blog post, Rules for Numbers.

In Conclusion

Punctuation and mechanics can be puzzling for business writers. Use AI checkers but remember they will not catch all your mistakes and they will falsely indicate mistakes. The best rule of thumb is to familiarize yourself with the rules and keep trusted resources bookmarked in your favorite browser.

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