Semicolon Usage Rules
Let’s talk about semicolons.
Punctuation is used to separate sentences, phrases, or words to further clarify a piece of writing. A semicolon, which looks like a period stacked on top of a comma, is used most commonly to join two independent clauses without using a coordinating conjunction.
Independent clauses are clauses that can stand alone in a sentence as a complete thought. An independent clause always has a subject, a verb, and a complete thought. An example of an independent clause would be the following sentence:
Bob went to the store.
The sentence needs no more explanation; it doesn’t leave us hanging. Dependent clauses have subjects and verbs too, but they don’t have complete thoughts. For example, look at this sentence:
Because Bob went to the store.
That is a dependent clause. It feels like it should have an ellipsis after it instead of a period, because the sentence isn’t finished. Because Bob went to the store…what? We don’t know, and that’s what makes it a dependent clause.
When you join independent clauses together, you normally have to use coordinating conjunctions. These are words that link other words, phrases or clauses together, words like “and,” “but,” and “yet.”
Now that we understand what an independent clause is and what a conjunction is, let’s look back at our definition of a semicolon: punctuation used most commonly to join two independent clauses together without using a conjunction.
Let’s take a look at a semicolon in action. Say you had the following two sentences:
Rina came home. She ate fried chicken for dinner.
A period is joining the two sentences, but if we used only periods as punctuation we would have only short, choppy sentences. Let’s join those two independent clauses up with a conjunction.
Rina came home, and she ate fried chicken for dinner.
To join two independent clauses together with a coordinating conjunction like “and” or “but,” you also have to use a comma before the conjunction. A comma is not sufficient by itself, and neither is the conjunction by itself.
But, here enters our heroic semicolon. It acts like both the comma and the conjunction working together. While it is not grammatically correct to write,
Rina came home, she ate fried chicken for dinner.
Rina came home and she ate fried chicken for dinner.
It is correct to write:
Rina came home; she ate fried chicken for dinner.
A semicolon, in this sense, functions as a “, and” in the sentence. Semicolons are stronger than a comma, but not as divisive as a period. Here are some other helpful rules to remember when using semicolons:
Delete the conjunction when using a semicolon. It’s never correct to have a semicolon with a conjunction following. If you choose to use a semicolon instead of a comma to connect two independent clauses, you have to get rid of the coordinating conjunction following the comma. A semicolon stands on its own!
Use semicolons to help with complicated lists. Sometimes you have to list things that have, within themselves, further clarifications. Semicolons can help with this. Look at the following sentence, for example:
I need the weather statistics for London, England; London, Ontario; Paris, France; Paris, Ontario.
The semicolons are separating the major cities, leaving room for the commas to serve as lesser dividers between each city and the country to which it belongs.
Use semicolons with conjunctive adverbs. Don’t get scared off by this new phrase. Conjunctive adverbs are exactly how they sound–adverbs that sometimes act as conjunctions. Think about words like “moreover,” “also,” “however,” etc. If you’re using some such word to connect two independent clauses, it’s much stronger to use a semicolon beforehand than a comma. Here’s an example.
I needed a walk and some fresh air; also, I needed milk.
The semicolon separates the first independent clause from the conjunctive adverb, which itself uses a comma to separate from the second independent clause.
Now that you have a firm grasp on all the good things semicolons can do, let’s go over a few things they can’t do. Firstly, a semicolon can’t separate an independent clause from a dependent one.
Although they tried; they failed.
This sentence is incorrect. “Although they tried” is a dependent clause because it does not contain a full thought. Therefore it can only be connected to the following independent clause with a comma, not a semicolon.
You should never capitalize words after a semicolon. Semicolons may be a stronger form of punctuation than a comma, but they still aren’t as significant of a pause as periods are. Clauses joined by semicolons are still within the same sentence.
Lastly, avoid the common misconception that semicolons and colons are interchangeable. Colons have two periods stacked on top of each other, and are often used to introduce or define something. They can be used to connect independent clauses with something as simple as a single noun, while semicolons can only connect two full independent clauses.
Well, that’s all for now – thanks for watching!