Before we go any further, you need to know that the
rules you are about to learn are based on what's in the AP
Stylebook. In other words, these are the rules that most newspapers
and many magazines follow, but they do not conform in every instance
with the rules that, for example, English professors or scholarly journals
may apply. The most important deviation occurs with items in a series.
Keep in mind that
in journalistic writing we are always concerned about saving space.
As a result, your guiding principle will be that you should ONLY
USE A COMMA IF YOU NEED TO. If none of these rules seems to
apply, resist the temptation to add a comma just because “it felt
like there needed to be one there.”
It may also help
for you to consider that commas are generally used in one of two ways.
First, they can serve to help connect different parts of a sentence.
In those cases, they appear singly. But they can also serve to place
certain parts of the sentence into the background. In those cases, they
appear in pairs.
You may not understand the grammatical
jargon that is used to state these rules. If you don't, click
on the rule to see examples and a fuller explanation.
No. 1: In a simple series, use a comma to separate the elements,
but don’t put a comma before the conjunction.
No. 2: Use a comma to separate two independent clauses connected
by a coordinating conjunction.
No. 3: Use a comma following an introductory clause or prepositional
phrase of four words or more.
No. 4: Use commas to set off modifiers that are not essential
to the reader's ability to identify a particular person, place
No. 5: Use commas to separate adjectives of equal rank.
No. 6: Use commas to set off words that add emphasis, shift
attention or provide a fuller explanation (parentheticals, "yes,"
"no," names in direct address).
No. 7: Use commas to set off participial modifiers that come
at the beginning of a sentence or after the verb.
No. 8: Use a comma, carefully, to set off quotes or paraphrases.
No. 9: Use a comma with hometowns, ages, years with months
and days, names of states and nations with cities, affiliations
and most large numbers.
No. 10: Use a comma to separate duplicate words to eliminate