Comma, Semi-Colons, and Periods—Which One?
A good rule of thumb a teacher in high school taught me: Whenever you feel like you need to take a breath or pause, you probably need punctuation of some sort. But which one? A period? A comma? A semi-colon? All three? Let’s define these three types of punctuation and when and how you should use them.
How to Use Commas
There are a few instances in which you can use a comma:
Lists: Use commas when you write out a list, and then always end that list with “text, and text”; the last item still needs a comma along with the word “and” (otherwise known as the ever-controversial Oxford Comma).
Example: I love cookies, brownies, and cake.
In place of parentheses: Sometimes, instead of using parenthesis, we can use commas to separate our thoughts.
Example: She liked, no, loved, cookies.
After a name: Whenever you address a person in writing, put a comma after it.
Example: Sally, can you pass the cookies?
After setting the scene: Whenever you start a sentence with setting the scene, put a comma after it.
Example: In the middle of the day in my house, I bake cookies.
How to Use Semi-Colons
Semi-colons are similar to em dashes; they signify a change in idea or another thought that doesn’t need a new sentence, yet is still different enough from the first idea that it needs more separation. Often, semi-colons and em-dashes are interchangeable.
Example: Sal never liked cookies; since an accident with the stomach bug in grade one, he’s stayed far away from them.
How to Use Periods
Periods are for when you have a completely different idea from the last one, or your sentence has simply become too long (there only so many times you can use a semi-colon before it becomes burdensome).
Example: Sal never liked cookies; since an accident with the stomach bug in grade one, he’s stayed far away from them. Not a single kind of cookie appeals to him!
Example of using all three punctuation marks in one sentence
“Sally loves cookies, but only fresh out of the oven; she hated when her mom put them in the fridge. Her mom enjoyed baking cookies every Saturday morning.”
How to Use Punctuation when Citing Biblical Texts
Another common area I see writers misuse punctuation is when citing biblical texts. Here’s a brief lesson:
When abbreviating a book of the Bible, use a period to communicate that it’s an abbreviation.
Use a colon between the chapter and the verse.
Use an en-dash to show a span between verses (if you quoted/referenced all the verses in between those two verses).
Use a comma to separate verses within the same chapter.
Use a semi-colon to separate chapters or books of the Bible.
Without any commas, only a space, reference the biblical translation you used in its abbreviated form.
Take out the punctuation at the end of the verse, put in your quotation marks, put your reference in parentheses after the quotation marks, and place a period at the end.
Example: “I can do all things through him who strengthens me” (Phil. 4:13).
Did you find this guide helpful? Even knowing the rules, sometimes we still make mistakes in our writing, especially in longer pieces like manuscripts. If you’d like another pair of eyes on your document to catch your grammatical errors, reach out!