Using Commas in a Series: Basic Rules
You’re probably familiar with the basic idea of using commas in a series, but here are some examples, just in case. You should use a comma to separate words, phrases, or clauses in a series. For example:
Each morning I jump out of bed, get dressed, brush my teeth, eat breakfast, and rush out the door.
When Kate went away for the weekend, she brought two shirts, two pairs of shorts, a pair of pajamas, a toothbrush, and clean underwear.
The Oxford Comma
This is one of the most misunderstood aspects of how to use commas in a series. The Oxford comma is the comma between the last two elements in a series. In the examples above, the Oxford comma is the comma between “eat breakfast” and “and rush out the door.” The Oxford comma got its name because editors at the Oxford Press encourage using it. Many newspapers do not use the Oxford comma, because omitting it saves room, which is hard to come by in the newspaper business. Keep in mind, however, that it should not be omitted in most academic writing.
Why is the Oxford comma (also called the “serial comma”) so important? Well, take a look at this example:
You can have one of the following for lunch: pancakes, macaroni and cheese, or toast and eggs.
Now read it without the additional comma. That additional comma can clear up a lot of unnecessary confusion, can’t it?
When is a list of adjectives considered a series? The best rule of thumb is to try putting the word “and” between the two adjectives. If it fits, then you can put a comma there instead. If it doesn’t, omit the comma. Here are a few examples:
The little old man lived in a brown log cabin.
The perky, energetic girl lived in a huge, luxurious house.
What’s the difference between these two sentences? First, look at the phrases “little old man” and “brown log cabin.” You wouldn’t normally say “the little and old man” or “the brown and log cabin,” so you would not put a comma between the two adjectives. On the other hand, you wouldn’t think twice about saying “The perky and energetic girl lived in a huge and luxurious house,” although it may sound a bit more concise without the extra conjunctions. Therefore, you can omit the “and”s and insert commas instead.