Comma refresher: how to use commas correctly


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I’m sure you’re most familiar with the use of a comma to indicate a small pause in a sentence. Sometimes the use of a comma comes down to personal preference, but getting it wrong can quickly change the entire meaning of a phrase.

Maybe you’ve even seen the meme about the importance of grammar which compares the phrases ‘let’s eat, grandma’ and ‘let’s eat grandma’. In this case, using a comma saves grandma's life. Admittedly, commas aren’t usually life or death but it’s a great example of how a sentence can be misunderstood.

Have you made your blog style guide yet? Check out this post to find out why you need one (and get a template to kickstart yours).

The comma is frequently used to break up the elements of a list. (That's where our Oxford Comma comes in.)

Commas can separate longer sentences or subordinate clauses linked by conjunctions like ‘and’, ‘but’, ‘yet’, and ‘or’. For example:

There were fireworks exploding nearby as we ate at the restaurant, but none of the other diners seemed to care.

The school has some of the most renowned teachers in the city, yet the students aren’t passing their exams.

However, it’s important not to separate the subject and verb. For example, don't use a comma in this context:

My friend Jane, is an excellent baker.

Reading that sentence probably felt a little clunky. If I’m unsure about whether to use a comma I generally try and read it with slightly more emphasis on the pause, then again without. Usually that will help signify if a comma is necessary.

Commas can replace brackets (parenthesis) in a sentence. For example:

Her new car, a red convertible, was stolen from the car park.

It’s important to remember this when adding commas. It's easy to accidentally create brackets where sentences should be split, or fail to include the second comma where needed.

When you’re unsure try reading the sentence without the information inside the paired commas/brackets. If the sentence still makes sense then you’ve used them correctly. If you’ve accidentally omitted important information, you’ll need to re-consider your structure.

Using commas in parenthetical elements can be one of the easiest ways to make your writing a little more personal. For example, you can use commas to add interruptions to a sentence.

There were, thankfully, no delays on our scheduled flights.

YBrand foundation, unlike XBrand, is easy to apply and lasts all night.

My baking skills, if you can even call them that, aren’t really up to scratch.

Commas should also be used when addressing someone or something. For example:

Come on, mum.

Give me a break, London.

Words like ‘as’, ‘since’, ‘while’ express time at the start of a sentence. But there's no need to use a comma unless the sentence is ambiguous. For example:

While we were walking to the park we saw workmen on the road nearby.

While we were walking to the park, the workman on the road nearby were having lunch.

However, clauses introduced by ‘as’, ‘since’, and ‘while’ should be followed by a comma.

Since you’ve driven so far, you may as well stay overnight.

Hopefully this quick and dirty guide has been a good refresher for using the basic comma. If you’ve got any specific questions, DM me on Twitter or Instagram and let me know.

Punctuation: how to use commas in your writing.