1. What is a Semicolon?
In writing, a semicolon (;) is a type of punctuation used to combine full sentences and share complicated lists. Semicolons let us clearly share two or more related ideas in one sentence, which keeps us from writing a bunch of short, awkward sentences about the same topic or thing.
A good way to think about a semicolon’s job is that it creates a stronger pause than a comma, but doesn’t demand a complete stop like a period!
Here are some examples of how we use semicolons to combine sentences and write out detailed lists:
- I love ice cream; it is my favorite food.
- I like cake; however, ice cream is my favorite dessert.
- I know great ice cream shops in Burlington, Vermont; Wickford, Rhode Island; Wakefield, Rhode Island; and Chester, New Jersey.
3. Ways to use Semicolons
Semicolons have two main functions: to combine full sentences, and to share complicated lists clearly. The correct ways to use them are pretty specific, which leads many writers to use them the wrong way or not at all. These sections will show you how to use them properly!
a. To Combine Full Sentences
A semicolon’s first job is to combine two or more independent clauses, putting together several full sentences about related things. You cannot use semicolons to combine an independent clause with a dependent clause, in other words, a complete sentence with an incomplete sentence (see How to Avoid Mistakes). There are two ways we use semicolons to combine independent clauses.
Combining two independent clauses
The first way to use a semicolon is right between two independent clauses (which each have a subject and a predicate), with no other connecting words. You should use a semicolon in this way when you want to share related things that are different but equally important, in one sentence instead of two (or more), like this:
- Dessert is the best meal of the day; it’s definitely my favorite!
- There is one thing I know; ice cream is the best dessert.
Each of the sentences above shares two independent thoughts related to dessert, and neither is particularly more important than the other. Semicolons are the best options here—a period would make them too choppy, and a comma would make a comma splice (see How to Avoid Mistakes). Also, notice that the word after the semicolon is not capitalized; unlike a period, there is no need to capitalize the first word after a semicolon.
Combining two independent clauses with a transition
You can also use a semicolon to combine two independent clauses that are separated by a conjunction, like however, thus, moreover, though, but, therefore, and so on, like this:
- Sometimes I have frozen yogurt; however, it’s not as good as ice cream.
- They were out of Rocky Road; thus, I was forced to choose another flavor.
These examples are similar to the way you combine clauses with only a semicolon; but, sometimes adding a transition word strengthens the meaning of the sentences. For example, using a semicolon and “thus” in the second sentence makes the speaker’s situation seem more dramatic, emphasizing the he really wanted Rocky Road.
Really, when you use a conjunction, it’s okay to use a comma instead of a semicolon. In those cases, the pause that the punctuation creates is up to the writer, and a semicolon is a bit more formal.
b. To List Things
A semicolon’s second job is to help make detailed lists. Sometimes we need to share a lot of detailed information in one sentence, and that can be confusing for readers if it isn’t punctuated the right way. Semicolons are very helpful for that situation! Here are some examples:
- John has lived in Atlanta, Georgia; Seattle, Washington; and Miami, Florida.
- Rocky Road has chocolate, peanuts, and marshmallows; Cookies and Cream has chocolate sandwich cookies; Neapolitan has chocolate, vanilla, and strawberry in one.
In the first sentence, the semicolons let you see the three detailed places where John has lived. The second clearly describes what’s in each of the different types of ice cream. The semicolons make these very descriptive sentences easy to understand—without them they would be pretty messy.
4. How to Avoid Mistakes
Semicolon mistakes are pretty common. But, these few things can help you avoid those mistakes in your writing:
a. Semicolons and colons are different!
A colon is different than a semicolon. The two have different jobs, and shouldn’t be used interchangeably. A colon lets the reader know that something else is coming after the first thought of a sentence. For instance, when a list is about to come, you need a colon, not a semicolon, like this:
- Jane likes three flavors: chocolate, vanilla, and strawberry. Correct!
- Jane likes three flavors; chocolate, vanilla, and strawberry. INCORRECT
To be clear, like in this example, colons can combine independent and dependent clauses, which semicolons cannot do (see below).
b. Semicolons and commas are different, too!
Today, a lot of people use commas instead of semicolons—sometimes that’s ok. But truly, commas have different jobs than semicolons, and there are some cases where you should use one and not the other.
For instance, when combining two independent clauses, if you aren’t using a transition, then you have to use a semicolon. Otherwise, you get a comma splice, like this:
- I love ice cream, I eat it every day. Comma splice, INCORRECT
- I love ice cream; I eat it every day. Correct!
Next, for simple lists, you only need to use commas, not semicolons; however, for more complicated lists, you should use semicolons, not commas. These sentences show why:
- My three favorite flavors are strawberry, chocolate, and vanilla.
- Jane likes her ice cream four ways: with hot fudge, cherries, and whipped cream; with caramel sauce, whipped cream, and bananas; with hot fudge and peanuts; and with just sprinkles.
As you can see, it’s definitely unnecessary to use semicolons in the first sentence because it only lists three simple things. But, the second sentence would be very confusing if it only used commas.
Finally, to combine independent and dependent clauses, you need a comma, not a semicolon. This leads us to the last rule:
c. A semicolon can’t combine an independent clause with a dependent clause.
As mentioned, when combining sentences you can only use semicolons to put independent clauses together, NOT to combine an independent clause with a dependent clause:
Yesterday after work; I ate three bowls of ice cream. INCORRECT
Yesterday after work, I ate three bowls of ice cream. Correct!
You can only use semicolons between independent clauses—complete sentences!