As a follow-up to the summer series on writing, this post is the first in a series providing technical advice on issues that graduate students (and others) run into in the revision stage. I’ll address problems I commonly see in drafts of dissertations and theses. For each item covered in the series, it’s important to keep in mind the three guiding principles for writers: genre, process, and audience. 

Genre: Most of the writing I work with follows APA or MLA style guidelines. Additionally, most of my writing students are at American institutions and follow those norms for writing. If your field requires a different style or if you are writing in a different academic context, always defer to that.  

Process: In the first stages of writing, trying to make each sentence perfect will only slow you down. The tips in this series are directed at the revision stage.   

Audience: The goal of writing is for your argument to be clear to your reader. Conventions like punctuation and table construction help guide your reader smoothly through your argument.  Sometimes, for clarity’s sake, you might choose to break a rule. That’s okay – these are conventions, not the first table of the Law. Just remember the goal, and make sure that when you depart from convention, it’s on purpose and for the right reason. (Laziness is rarely the right reason.) 

On the topic of clarity, this is what no less of an authority than the website of the Chicago Manual of Style has to say about a (very) sacred cow of many editors, the serial comma: “there are times when using the comma (or omitting it) results in ambiguity, which is why it’s best to stay flexible.” Amen. 

That’s quite enough preamble for one post . . . on to the comma.  

What Are Commas For? 

It was maybe when I was in high school that I had a teacher call me out on my overuse of commas. That punctuation mark, she informed me, operated according to specific rules and was not to be thrown in willy-nilly wherever I thought there should be a pause in the sentence. This was perhaps the same teacher who wrote in large red letters at the end of one of my papers: “it’s = it is” (an admonishment that I have never forgotten).  

My teacher was right about the contraction, but I take issue with her comma perspective. I agree that one must not simply toss commas into sentences like so much parmesan cheese. But I disagree about the comma-pause connection. A comma is indeed a pause for the reader, an indication of a break or separation in the progression of thought. Keeping in mind the principle of clarity, the trick is to make sure your commas are pauses with a purpose. 

When to Use Commas 

Probably more rules exist for the use of commas than for any other punctuation mark. But if you keep in mind five main comma guidelines and pair these with attention to your reader’s understanding, you will have plenty to be going on with.  

Rule One: Items in a Series 

Use commas after items in a series of three or more, including a comma before the coordinating conjunction (usually and).  

Examples 

Most participants in the study were male, married, and living in the southwestern United States. 

I posted the invitation to participate on LinkedIn, collected the names and demographic information of likely participants, and selected those most suited to the purposes of the research. 

This rule supports the famed serial comma, also known as the Oxford Comma and Harvard Comma. I am a big fan (and APA, MLA, and Chicago all recommend it), but this comma usage is the subject of fierce debate. Following that rabbit trail can be a great procrastination technique if you are a punctuation nerd. But don’t be; save yourself time by inserting that comma and moving on. 

Rule Two: Separate Adjectives 

Use commas to separate adjectives that equally modify a noun. 

Example 

The research site is an established, upscale supermarket in an urban neighborhood. 

How do you know if the adjectives (“established” and “upscale”) equally modify the noun (“supermarket”)? Use this test: Can you reverse their order and write, “an upscale, established supermarket”? Could you insert an “and” between them and say, “an established and upscale supermarket”? You can, so they are equal.  

Here is an example of adjectives that do not equally modify the noun: 

The study focused on analyzing the impact of various complex social dynamics on urban communities.  

“Complex, various”? “Various and complex”? Nope. So no comma. 

Rule Three: Commas and Coordinating Conjunctions 

The coordinating conjunctions are: for, and, nor, but, or, yet, and so. You may recall from the murky past of your grammar school days that you can remember this list by the acronym FANBOYS. Use a comma before a coordinating conjunction if what is on either side is an independent clause. What is an independent clause, you ask? An independent clause is a group of words with a subject and verb that can stand on its own as a sentence. 

Example

The literature on student cheating often mentions plagiarism, but it does not always define the term. 

Note that both “The literature on student cheating often mentions plagiarism” and “It does not always define the term” could be sentences. The following use of a coordinating conjunction does not require a comma: 

The literature on student cheating often mentions plagiarism but does not always define the term.  

There is no subject in the group of words after the conjunction (“does not always define the term”), so there is no comma. 

Rule Four: Non-Essential Elements 

Use commas around elements that are not necessary to the meaning of a sentence.  

Examples 

The author, who is a professor at the Harvard Kennedy School of Business, has published many works on the same topic. 

I allowed each participant to read over the transcript of their interview, which is called member checking. 

Think of the commas in this case as being little hooks, with which you could lift the enclosed words out of the sentence without changing the meaning. In the second example, the non-essential element is the remainder of the sentence after the comma, which is the only reason to not use a second comma when following this rule. 

Sometimes, determining whether an element is essential depends on context. For example, if you are writing about several authors, one of whom is a professor at the Kennedy School, and you need to distinguish the authors using that information, you would write: 

The author who is a professor at the Harvard Kennedy School of Business . . .  (as opposed to the author who is a research chemist at Johnson & Johnson). 

Here again, clarity is the beacon that should guide you. 

Rule Five: Introductory Elements 

Use a comma after an introductory word, phrase, or clause. 

Examples 

First, I constructed a survey. 

Before I conducted each interview, I asked the participants if they had any questions. 

In a similar argument, Blaise (2019) suggested that mentoring has both social and academic benefits. 

While several authors suggest that research should explore the relationship between early mentoring and college retention, few such studies seem to exist. 

And That, as They Say, Is That 

Keeping these five guidelines in mind should get you through most comma revisions. For all other comma-related conundrums, I suggest you place a sticky note in section 6.3 of your APA 7 or the corresponding spot in other style guides!   

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