1. Should I use a comma
before and in a series?
It’s your choice. Most
business writers prefer to use the “serial comma” before and in a
series of three or more items. For example, “I like carrots, broccoli,
and succotash.” Most newspapers, however, omit the comma before and.
Whatever your preference, be consistent. Also, be sure to use the style of the
publication or organization for which you are writing. (Rule 162, p. 35; also,
see The Associated Press Stylebook and Libel Manual, p. 269.)
2. Should I use a comma
when the conjunction and joins two clauses in a sentence?
Use a comma when and joins
two clauses consisting of two subjects and two verbs; omit the comma when and
joins two verbs that have the same subject. For example, “She wrote the memo,
and she sent it,” but “She wrote the memo and sent it.” (Rule 123, p. 14).
Note: The comma in the first example may be omitted when the clauses are
3. When should I use
commas with that and which?
Introduce a restrictive or
essential clause with that and do not mark it with a comma or commas.
For example, “Sally wrote the report that was approved. Susan wrote the
report that was rejected.” Introduce a nonrestrictive or nonessential
clause with which and mark it with commas. For example, “Sally’s report,
which was approved, was the only one considered.” (Rule 131, p. 19, and
Rule 1062, p. 237)
4. Should I use commas
before and after the year in a date?
Yes. Use two commas to set
off the year when it follows the month and day and the sentence continues, as
in “August 15, 1997, was a scorcher.” But note: “August 1997 was an unusually
warm month.” (Rule 154, p. 33)
5. What is a “comma
splice,” why is it a problem, and how can I avoid it?
A “comma splice” occurs
when two complete sentences are joined (or spliced together) with a comma
rather than with a concluding punctuation mark such as a period or a
semicolon. In informal writing such as popular fiction, comma splices are
common (especially in dialogue), but in on-the-job writing (business writing,
technical writing, legal writing, academic writing, journalism, etc.) they are
considered a distracting error. Readers generally want to know where one
sentence ends and the next begins. The most common comma splice occurs when
the adverb however is mistaken for a conjunction. For example, change
“I only wanted to help, however, I hurt his feelings” to “I only wanted to
help; however, I hurt his feelings” or to “I only wanted to help, but I hurt
his feelings.” When two complete sentences are linked by a transitional
expression such as however and therefore, use a semicolon – not
a comma – between the sentences; use a comma after the transitional
expression. (Rule 178, p. 40)
6. Should I use
one space or two after periods and colons?
The trend is to use only one space after
these marks, although some style manuals still call for two. The main
thing is to space consistently throughout a document.
In his widely used reference guide, The
Gregg Reference Manual, William Sabin calls for two spaces. But in The
Mac Is Not a Typewriter, Robin Williams (not the actor) calls for one. The
argument for one space is that kerning, or spacing between words,
automatically allows for a little extra space after periods and colons.
Note that most e-mail software will transmit only one space anyway (perhaps to
minimize transmission time).
Nevertheless, because I
think the extra white space opens the text and makes it look more inviting to
the reader, my personal preference is
for two spaces. I suppose I’ll
eventually give in and use just one space.
7. Do commas and periods
go inside or outside the closing quotation mark?
According to American usage
(which differs from the “British style”), commas and periods go inside the
closing quotation mark. Other punctuation marks (such as question marks,
colons, and semicolons) go inside or outside, depending on whether they are
part of the quoted material.
Some writers and language
experts argue that commas and periods, when not part of the quoted material,
are more logically placed outside the closing quotation mark. Standard
American usage, however, is based on the notion that placing commas and
periods within the closing quotation mark causes no significant confusion or