Semicolons are used to join two independent clauses without the use of a coordinating conjunction. There are two ways to use a semicolon to join independent clauses.
1. Use just the semicolon. If the main idea between the two clauses is obvious, you can separate the independent clauses using only a semicolon.
John and Bill work well together; they always ace their assignments.2. Follow the semicolon with a transition (grammatically known as a conjunctive adverb). Follow the transition with a comma.
John and Bill work well together; thus, they always ace their assignments.It is also acceptable to drop the comma if the writer wishes to eliminate the implied pause.
John and Bill work well together; thus they always ace their assignments.Coordinating conjunctions
You can also use a semicolon to join independent clauses with a coordinating conjunction if your sentence is already weighed down by commas.
American Idol, the number one show on Fox, is an energetic, exciting, and entertaining television show; but sometimes the judges, though honest, can be cruel.To replace a series comma
If your series contains commas, you will want to separate the series with semicolons rather than commas.
John owns homes in Orlando, Florida; Denver, Colorado; and San Francisco, California.