Unnecessary semicolons

No semicolon between a subordinate clause and the rest of the sentence

Example sentence with editing. Original sentence: Unless you brush your teeth within ten or fifteen minutes after eating; brushing does almost no good. Revised sentence: Unless you brush your teeth within ten or fifteen minutes after eating, brushing does almost no good.

No semicolon between an appositive and the word it refers to

Example sentence with editing. Original sentence: The scientists were fascinated by the species Argyroneta acquatica; a spider that lives underwater. Revised sentence: The scientists were fascinated by the species Argyroneta acquatica, a spider that lives underwater.

No semicolon to introduce a list

Example sentence with editing. Original sentence: Some of my favorite film stars have home pages on the Web, Uma Thurman, Billy Bob Thornton, and Halle Berry. Revised sentence: Some of my favorite film stars have home pages on the Web: Uma Thurman, Billy Bob Thornton, and Halle Berry.

No semicolon between independent clauses joined by and, but, or, nor, for, so, or yet

Example sentence with editing. Original sentence: Five of the applicants had worked with spreadsheets; but only one was familiar with database management. Revised sentence: Five of the applicants had worked with spreadsheets, but only one was familiar with database management.

EXCEPTIONS:If at least one of the independent clauses contains internal punctuation, you may use a semicolon even though the clauses are joined with a coordinating conjunction.

Example sentence: As a vehicle [the model T] was hard-working, commonplace, and heroic; and it often seemed to transmit those qualities to the person who rode in it.

Although a comma would also be correct in this sentence, the semicolon is more effective, for it indicates the relative weights of the pauses.

Exercise: The semicolon and the comma 1

Exercise: The semicolon and the comma 2

Exercise: The colon, the semicolon, and the comma