Clauses, conjunctives, and conditions

Most writers I know have a love-hate relationship with commas, omitting them where they should be added and adding them where they should be omitted. As a line editor, the most common punctuation issues I see stem from incorrect comma use.

So, how do you use commas correctly?

Let me guide you through the next step of your journey toward punctuation perfection.

A glossary of terms I’ll be using in this guide

Clause: the basic unit of grammar. Clauses must contain a verb.

* independent clause: contains a subject (more on those below) and a verb phrase.

e.g. “He picked up the box.”

* dependent clause: contains a subject and a verb, but does not contain a complete thought.

e.g. “Picking up the box.”

“Because he picked up the box.”

“While he picked up the box.”

* Note: a dependent clause by itself, as shown in the examples above, is an example of a sentence fragment.

Subject: the noun (person, place, or thing) which performs the verb action in the sentence.

e.g. “[He] picked up the box.”

“[She and her friends] went to the movies.”

“[The owls living in my attic] caused a ruckus.”

Predicate: the sentence part which contains the verb and states something about the subject. In other words, a predicate is any part of the sentence EXCEPT the subject.

e.g. “He [picked up the box].”

“She and her friends [went to the movies].”

“The owls living in my attic [caused a ruckus].”

Other terms will be defined throughout.

When to use commas before joining words (i.e. and, but, yet, nor, or, and so)

Sentences made of two independent clauses need a comma before the joining word (known as a ‘conjunction’).

e.g. “[He picked up the box], and [his sister opened the cupboard].”

Compound predicates (predicates containing two or more details about the same subject and two or more verbs joined by a conjunction) should not use commas.

e.g. “He [picked up the box and placed it next to him].”

“She [put the car in reverse and backed into the parking spot].”

Splices: great for wires, not-so-great for commas.

Examples of comma splices and how to avoid them

A comma splice refers to the incorrect usage of a comma to join two independent clauses.

e.g. “He went to the store, it was closed.”

“The fair was a lot of fun, we had a good time.”

Fix a comma splice by using a semicolon or a conjunction in place of a comma, or by starting a new sentence.

e.g. “He went to the store; it was closed.”

“The fair was a lot of fun, and we had a good time.”

“The fair was a lot of fun. We had a good time.”

Use a comma when directly addressing a person by name or title in dialogue

e.g. “Isn’t that right, Abigail?”

“Hey, Javier, where are you going?”

“Captain, what are your orders?”

“Don’t ask me, Lieutenant.”

(side note: always capitalize titles when using them as name replacements.)

How to use a comma when referring to people by name or title in a sentence

DON’T use a comma when the name or title is essential to clarify meaning.

e.g. “My daughter Annabelle wrote an article.”

“The article was written by my daughter Annabelle.”

These sentences indicate the speaker has more than one daughter, and each specifies which one.

DO use a comma when the inclusion of the name or title is irrelevant to understanding the sentence.

e.g. “My brother, Mark, told me to try this brand instead.”

“I was told to try this brand by my brother, Mark.”

The above examples imply that the speaker only has one brother, and his name is Mark. You don’t need to know Mark’s name to understand that he is the person to whom the speaker is referring.

Homework: read up on these types of phrases, known as “nonrestrictive appositive nouns.”

Like an establishing shot in cinema, an introductory clause provides setting details and context to stoke the imaginations of your readers.

Use a comma after starting a sentence with an introductory (establishing) clause or a conditional statement

In other words, use commas after phrases which, at the beginning of the sentence, specify position, time or range of time, reason, method, or condition.

Examples of sentences with establishing clauses:

• Position or ‘where’:

“At the foot of the mountain, we double-checked our gear.”

“In my attic, an owl hooted.”

“Ever since I was young, I’ve had an interest in writing.”

“At four in the morning, I had an epiphany.”

• Reason, or ‘why’:

“Because of my injury, I couldn’t go on the hike.”

• Method, or ‘how’:

“With a mighty roar, the lion swiped at the water buffalo.”

“By working together, we managed to clean the kitchen in time.”

• Condition, or ‘if’:

“If I could go to sleep sooner, I wouldn’t be so tired in the morning.”

Use commas between coordinate adjectives

A coordinate adjective is a set of descriptors that equally modify a noun.

e.g. “I saw the annoying, scary owls in my attic.”

Don’t use commas between cumulative adjectives, which are a series of descriptors which build on each other to provide the correct meaning.

e.g. “She was a sweet little old Spanish lady.”

The descriptors in a cumulative adjective must be presented in this order:

• Opinion (e.g. sweet)
• Size (e.g. small)
• Age/condition (e.g. old/worn)
• Length/shape (e.g. square)
• Color (purple, cyan, magenta)
• Origin/nationality/religion (“Spanish”)
• Material (plastic, wooden)
• Purpose (“hockey” jersey)

In the example I used for the coordinate adjective, “I saw the annoying, scary owls in my attic”, both “annoying” and “scary” come from the same adjective category. Neither descriptor is necessary for the reader to understand that there are owls in my attic; they simply add flavour to the statement.

In summary

Use commas when you:

• join two independent clauses with a conjunctive, such as ‘and’, ‘but’, or ‘so’.
• directly address a person by name or title in dialogue
• refer to a person by name or title, and those details are not contextually important to the understanding of the sentence
• use an introductory statement to establish where, when, why, how, or if the action occurs
• describe a noun using multiple adjectives from the same category

Thank you for reading! If you found this guide helpful, please share it with the authors in your life. You can also find me on Medium.