I’m less clear on semicolons than I am with respect to commas. I just thought they’re commas with a period on top.

Semicolons separate things. Most commonly, they separate two main clauses that are closely related to each other but could stand on their own as sentences if you wanted them to. For example: I ‘m going to the baseball game; I can’t get together with you tonight.

That can also be: I’m going to the baseball game.  I can’t get together with you tonight. So, why use the semicolon then? Well, you might have too many short choppy sentences. More important is that it allows you to link two related clauses.

Never use a semicolon with a coordinating conjunction such as “and,” “so,” and “but” to join two main clauses. You use a comma for that. For example: I’m going to the baseball game, so I can’t get together with you tonight.

But then there are exceptions. Yeah, the English language is so confusing. First, if you have a long sentence with multiple independent clauses, and some of those clauses contain internal punctuation such as a comma, you can use a semicolon with a coordinating conjunction to make the separation between clauses more clear. Here’s an example: If you want me to go out tonight, you need to find some to take my baseball tickets first; and if you say no, I’ll know that you don’t really want to go out.

Here is another instance in which you can use a semicolon with a coordinating conjunction. That’s when you have an excess of commas: it’s when you need to separate list elements that contain commas. Here’s an example: The all-star lineup includes Sidney Crosby from Pittsburgh, Pennsylvania; Jamie Benn from Dallas, Texas; and Patrick Kane from Chicago, Illinois.

Notice again that both times you can use a semicolon with a coordinating conjunction such as “and,” it’s because commas are already being used for something else, so using a comma could be confusing to readers.

Finally, you use a semicolon when you use a conjunctive adverb or transitional phrase to join two main clauses.

Conjunctive adverbs are words such as “however,” “therefore,” and “indeed,” and they “usually show cause and effect, sequence, contrast, comparison, or other relationships”. For example: I ‘m going to the baseball game; therefore, I can’t get together with you tonight.  (The comma after the conjunctive adverb is optional.)

A transitional phrase is something like “for example” or “in other words.” A sentence with a transitional phrase could read as follows: I ‘m going to the baseball game; as a result, I can’t get together with you tonight.

I know it’s all so confusing. If you can’t keep the difference straight in your head, it can help to remember that commas are smaller than semicolons and go with coordinating conjunctions, which are almost always short two- or three-letter words—small words, small punctuation mark.

Semicolons are bigger and they go with conjunctive adverbs and transitional phrases, which are almost always longer than three letters—bigger words, bigger punctuation.