Grammar Minute – Offsetting Phrases

One of the most common places where I see misused punctuation while reading and editing books is around what I tend to call interjections but are more accurately classified as parenthetical phrases. There are a few options for how to offset those phrases, and as long as you’re consistent, you can choose whichever one works best for you.

First, what is a parenthetical phrase?
When you interrupt a sentence to give the reader more information about something, you’re using a parenthetical phrase. The phrase could be an aside, an interjection, an appositive, etc. The common thread is that it’s not necessary to the overall sentence.

There are three main ways to offset these phrases. As a self-published author, you get to pick what fits your writing style best.

  1. Offset using commas
  2. Offset using dashes (stay tuned for my next blog post if you like dashes)
  3. Offset within parentheses

That being said, there are some sentences that lend themselves more naturally to dashes or parentheses rather than commas.

Here’s my trick: if any of the following things are true, don’t use commas to offset your aside/interjection/parenthetical phrase.

  • There are commas within the offset phrase. 
  • The sentence would need a comma where you’re splitting it with the offset phrase.
  • The offset phrase is directed at the reader (breaking down the 4th wall).

If you are using dashes to offset your phrase, you MUST end the offset phrase with another dash, NOT a comma. If you are using commas to offset your phrase, you MUST end the offset phrase with another comma.


My celebratory lunch, which really was just a sandwich, tasted fantastic.

Believe it or notand really, I think anyone would believe itI didn’t want to go dancing.

She finished her dinner (read: she ate two bites and said she was full) before everyone else.

Her favorite booknot including her own, of coursewas written over 50 years ago.

The good news is that the more you find and fix this error in your writing, the more natural it will become to use consistent punctuation. With that in mind, here’s your opportunity to get more comfortable with using commas with interjections/appositives/asides/parenthetical phrases correctly:

Your “homework”:

  1. Pick one (unedited) chapter to check.
  2. Read through sentence by sentence, identifying any phrases that are offset by commas or dashes.
  3. Find the beginning and end of each phrase and make sure they’re offset by the same type of punctuation.
  4. If the sentence and/or phrase has commas, update the punctuation around the phrase to be dashes or parentheses.
  5. Fix any errors you find. If you get stuck, send questions my way; I’m happy to help!
  6. Enjoy the feeling of knowing your book is even better than it was before!

Paige K

What are your grammar hang-ups? Let me know, and you may see them featured in future blog posts.

Are you an author?

If you’re interested in having a sample of your work edited by a copy editor, free of charge, this is your chance. Let’s see if we’re a good fit for each other. Working with an editor is the best way to get your book to where you want it to be.

Subscribe to the Grammar Minute

We'll never share your information. You'll also receive resources & exclusive offers. Privacy Policy

This website uses cookies to ensure you get the best experience on our website.