Learn the effective use of semicolons.
This handout explains the purpose of a semicolon [;], which is used to join together complete sentence parts.
Semicolons are often used to correct comma splices, which is what happens when we connect two independent clauses with a comma when there is no coordinating conjunction:
This sentence contains a comma splice. While the instinct in correcting comma splices is to use a semicolon here, simply adding a coordinating conjunction would correct the comma splice:
One common mistake is to use words like “however” or “therefore” as coordinating conjunctions. However, they are not. When connecting two independent clauses with a comma and a word like “however” or “therefore,” you can either divide the sentence into two sentences, or use a semicolon, which can be used to connect two independent clauses without a coordinating conjunction.
If you are unsure whether to use a comma or semicolon, check if both sides are independent clauses, or what can stand on their own as sentences. If both sides are independent clauses, you either need a semicolon or a coordinating conjunction. If only one side is an independent clause, and the other is a dependent clauses, use a comma.
If you are unsure whether to use a semicolon or period, think about why you want to join the two ideas together in the first place: should they be in the same sentence or in separate sentences?