Grammar Smart 3rd Edition - Princeton Review 2014

E. The Semicolon
PART 4. Punctuation

For some reason the semicolon is the most feared punctuation mark; it seems to inspire loss of confidence even in accomplished writers. The rules for semicolons are simple.

Rules For Semicolons

1. Use a semicolon to link two independent clauses.

To give a good party, you must consider the lighting; no one feels comfortable under the bright glare of fluorescent lights.

Note that the two clauses are connected in thought. Also—and this is the thing to understand about semicolons—you could use a comma and a conjunction in place of the semicolon.

To give a good party, you must consider the lighting, since no one feels comfortable under the bright glare of fluorescent lights.

2. Use a semicolon to separate elements in a list if the elements are long or if the elements themselves have commas in them.

To get completely ready for your party, you should clean your house; make sure your old, decrepit stereo works; prepare a lot of delicious, strange food; and expect odd, antisocial, and frivolous behavior on the part of your guests.

3. Semicolons belong outside quotation marks.

One man at the party sat in a corner and read “The Adventures of Bob”; he may have been shy, or he may have found “The Adventures of Bob” too exciting to put down.