Q. Can you help me out with a question? Do you use a comma after the abbreviation of the word incorporated? For example, in the sentence “Today, ABC Company, Inc., announced that their earnings have increased 50 percent in the past year,” we have been told to use a comma after the word “Inc.” when used in a sentence. This has caused an uproar within the company because we did not learn this rule. Help!

Q. In our international magazine mailings, we always include the country name; however, we would like to know the correct procedure for including “USA” after the city/state/ZIP. Is there a comma after the ZIP code or not? Your assistance would greatly reduce the amount of tension/dissension among the writers and editor and proofreader.

Q. If you say “so-and-so is vice president, finance, of such and such,” should there be a comma after “finance”? My boss and I are in disagreement. I think there should be a comma but she says no. I can’t find a specific reference to this anywhere, though.

Q. What is a “restrictive” appositive? I have read paragraphs 5.21 and 6.26, but I do not understand the difference between the two types of examples, distinguishing the use of commas by this term. Please advise . . . my client wants to know the “why” behind my editorial source.

Q. I totally agree with Chicago’s use of the serial comma. However, I am creating a style guide for a company that does not use the serial comma. For the sake of consistency, I am considering stating in the guide that the serial comma is not to be used at all (yikes!). My question is: Is it better to be consistent (and not use the serial comma at all) OR to add in the serial comma ONLY when it is necessary to prevent ambiguity? I wish that I could just DEMAND the use of the serial comma at all times, but alas, I am just a lowly intern. Thanks a lot for your help!

Q. Are phrases regarding the location of something deemed restrictive or not? Must one know whether only one exists in order to insert commas? I know it is always “the White House, in Washington, D.C.” But must it also then be “Bob’s Hardware in Dallas” when I do not know if there are other places that go by the same name? If I encountered “Bob’s upstairs neighbor Bill,” and didn’t know if he lived below one person or on the second floor of a ten-story building, I would have to make it restrictive, yes? So wouldn’t the same rule apply here? I work for a weekly magazine without a research department and this question has been preying on my frazzled mind for some time—please help!

Q. I seem to be alone in my habit of including a comma in e-mail greetings that begin with a salutation (e.g., “Hi, Mom!”). Most people, perhaps inspired by the more formal “Dear Mom,” seem to think it should be without comma. What do you think?

Q. I always use commas in serial lists. However, if I am referring to an entity that does not use the comma in its name, should I add it for consistency? Should the Columbia University School of Architecture, Planning and Preservation become the School of Architecture, Planning, and Preservation? Similarly, the Chicago Manual recommends no comma before “Inc.” If I am referring to an old firm that used the comma, should I delete it? Should Louis Sherry, Inc. become Louis Sherry Inc.?

Q. What is the proper comma usage in describing a series of nouns with a single adjective? For example, “This spring’s collection emphasizes sexy lingerie, blouses, skirts, and mukluks.” I am devoted to the serial comma, but should a comma be included after the third item if I want the adjective to apply to all four items? I write for an online retailer and often find myself stumped by this little conundrum.

Q. Is it correct or incorrect to put a comma before the “and” in the following sentence: “The Department of Justice has taken on the role of coordinating agencies’ activities, and has undertaken several new initiatives related to dealing with criminals.” I think it’s correct because the second clause—although not an independent clause, strictly speaking—is so long (and the subject is implied). The comma seems to help the reader get through the sentence. Many thanks.