To me commas are magic grammar glitter. The editor throws them at the page, and ‘poof’ they fall into place. Having done a bit of research on them and their various rules, I decided to break it into many parts.

The first one I am very comfortable using: commas are used to separate things/verbs in a series.

Example: A triathlon is comprised of running, swimming and biking.
Example: I need to pick up milk, butter, macaroni, and cheese from the grocery store.

Simple and neat. I’m going to the store to pick up four things. I could also have written it like this:

Example: I need to pick up milk, butter, and macaroni and cheese from the grocery store.

Now, I’m only picking up three things since the macaroni and cheese can be considered one item. I know what you’re thinking–Lots of editors don’t have a problem leaving off the last comma as it doesn’t really changing the meaning. And you’re right, but I like to keep things simple. The editor can change the punctuation to her/his preferences.

Comma use #2- a comma and a conjunction connects two complete sentences. This one my word processor usually catches me on. The conjunctions in this case are: and, but, or, for, nor, yet and so.

Example: I’m going to the store, and he’s going to the movies.

‘I’m going to the store’ is a complete sentence. ‘He’s going to the movies’ is a complete sentence. Both can be written as such but an integral part of pacing is to vary sentence length. So sometimes you’ll want to join two complete sentences.

Incorrect use: The dog ran through the surf and then shook water on us.

‘Then shook water on us’ is not a complete sentence, so there would be no comma.

Those two things are easy and I should be able to remember the last one, but on reviewing this entry I think I need to look at how to use parentheses correctly.