Grammar Minute – Whose Comma

One of the biggest grammar pain points for any writer is commas. The majority of edits I suggest in any book are adding and removing commas. I can’t address all the places you should and shouldn’t use commas in one post, so my focus here is on whether or not to use a comma before “who” in a sentence. The placement of a comma there actually changes the meaning of the sentence, and these commas are easy to search for and fix, so this comma is a good one to start with.

So what is the difference?

Whether or not to use a comma before “who” depends on how many people you could be talking about. 

One person: when it is already clear who the sentence is talking about, use a comma
The phrase starting with “who” is providing additional information about a known person.
ex. “My brother, who likes to read, is over there.”
Because the comma is there, a reader can infer that you only have one brother.

Two or more people: when you are clarifying which person the sentence references, do NOT use a comma
The phrase starting with “who” is helping the reader identify who you are talking about.
ex. “My brother who likes to read is over there”
Because there is no comma, a reader can infer that you have multiple brothers, and the one who likes to read is over there.

Here’s my trick: try taking out the descriptor starting with “who.” 
If the reader will still know exactly who you’re talking about, then you should use a comma.
If the reader now has to guess who you’re talking about, then you should NOT use a comma.

This can also be used to determine whether to use a comma before “which” or “whose.”

More examples:
The painting, which is by the door, is one of my favorites. → There is one painting
The painting which is by the door is one of my favorites. → There are multiple paintings
I invited my neighbor, whose hair is red. → There is one neighbor
I invited my neighbor whose hair is red. → There are multiple neighbors

The good news is that the more you find and fix this error in your writing, the more natural it will become to keep or remove the comma. With that in mind, here’s your opportunity to get more comfortable with using commas with who/which/whose correctly:

Your “homework”:

1. Pick one (unedited) book to check.
2. Search for instances of “who,” “which,” and “whose.” (Narrow your search by adding spaces before and after)
3. Take out the phrase starting with  “who,” “which,” or “whose” to determine whether or not you need a comma.
4. Fix any errors you find. If you get stuck, send questions my way; I’m happy to help!
5. 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.

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