Commas – when you absolutely positively have to use them

I know. You saw the title of this post and immediately thought WTF . . . or something along those lines. After all, way back in this post, I said commas were basically speed bumps and that the rules were basically guidelines.

And that’s still true, but I also said you don’t want to go all nuts and just drop all the commas in your manuscript. Trust me; don’t do it. That way lies insanity.

So, you need commas . . . but not all the time. How do you figure out when you definitely absolutely positively have to have them? By using these little things known as style guides.

Style guides help you keep your writing consistent, and consistency is the #1 thing you want to keep your eye when writing your manuscript. Okay, interesting characters and an exciting plot are actually the #1 thing when it comes to writing . . . but consistency is the #1 thing when it comes to editing, because you don’t want Abby the Sassy Witch to have red hair on page 3 and blonde hair on page 12, and you also don’t want to use a serial comma in the first half of your book but not in the last half. Readers will notice, and they’ll wonder which part you screwed up on. Even if they don’t actually know what a serial comma is, they’ll notice that it either appeared or disappeared halfway through your book.

Also, it just so happens that the serial comma is a great example about the rules regarding comma use. Why? Because some style guides (like the Chicago Manual of Style) say to use it, while others (like the Associated Press Style Guide) say to not use it. Which guide do you listen to? It mainly depends on what you’re writing. If you’re a journalist or news blogger, you’ll probably want to skip the serial comma because journalists tend to use the Associated Press Style Guide. If you’re a fiction writer, you’ll want to use the serial comma because the Chicago Manual of Style says the serial comma is great. Not cheesecake great, but still great.

Mmmmm. Cheesecake.

Okay, where was I? Oh yeah; commas.

So, you’re a fiction writer using the Chicago Manual of Style (lovingly referred to as CMOS). That makes it easy to decide when to use commas, because good ol’ CMOS tells you.

There are a lot of rules regarding commas, but as a writer of fiction, there are a few situations that you’ll probably encounter on a regular basis:

Serial commas

When a conjunction joins the last two elements in a series of three or more, a comma—known as the serial or series comma or the Oxford comma—should appear before the conjunction.

Commas with independent clauses joined by coordinating conjunctions

When independent clauses are joined by and, but, or, so, yet, or any other coordinating conjunction, a comma usually precedes the conjunction. If the clauses are very short and closely connected, the comma may be omitted unless the clauses are part of a series.

He went to the store, but couldn’t remember what he went there for.

Commas with compound predicates

A comma is not normally used to separate a two-part compound predicate joined by a coordinating conjunction. However, a comma may occasionally be needed to prevent a misreading, so you can have something like this–

He printed out a week’s worth of crossword puzzles and arranged them on his clipboard.

or this

She recognized the man who entered the room, and gasped. (The comma is needed in this case to let the reader know she gasped. Otherwise it would look like the man entered the room and gasped)

While we’re on this subject, let’s have a quick talk about and then. MS Word LOVES and then. Specifically, MS Word has a big ol’ crush on and.

When then is used as a shorthand for and then, a comma usually precedes the adverb.

He took his seat on the bus and then pulled out his Kindle.


He took his seat on the bus, then pulled out his Kindle.

MS Word will insist that you change that last sentence to ‘He took his seat on the bus, and then pulled out his Kindle.’ Does that work? Sure it does, but it’s not necessary so feel free to ignore that little helpful suggestion from Word.

Commas with introductory dependent clauses

When a dependent clause precedes the main, independent clause, it should be followed by a comma. A dependent clause is generally introduced by a subordinating conjunction such as if, because, or when.

If you see things our way, you’ll find that life will be a lot less painful for you.

Commas with coordinate adjectives

As a general rule, when a noun is preceded by two or more adjectives that could, without affecting the meaning, be joined by and, the adjectives are separated by commas. Otherwise, no commas are used, so you can have–

It was going to be a cold, brutal winter. (It was going to be a cold and brutal winter.)


She wore her little black dress on their first date. (She wore her little and black dress on their first date?? Nope.)

Commas with “too” and “either”

This one is a bit of a bugaboo because I think the rule changed at some point. I vaguely remember being taught to use a comma when a sentence ended with too or either when I was in school, but that was then and this is now.

The adverbs too and either used in the sense of “also” generally need not be preceded by a comma, so–

I like comic books and superhero movies too.

I don’t like broccoli; my brother doesn’t either.

So, I think that about covers the comma. Good ol’ CMOS has a few more rules, but I think the situations above are the ones that fiction authors will encounter on a regular basis.