Set off an adverb clause at the beginning of a sentence. An adverb clause begins with a subordinating a conjuntion, such as after, although, as, because, before, if, since, though, unless, until, when, whenever, where, wherever, or while.
Rule 10 Example
Whenever I feel afraid,
I whistle a happy tune.
Set off a nonessential adjective clause. A nonessential adjective clause simply gives additional information and is not necessary to the meaning of a sentence.
An adjective clause usually begins with a relative pronoun, such as who, whom, whose, which, or that.
Rule 11 Example
My house, which has green shutters, is at the corner of Elm and Maple.
Hint: If your not sure if it needs a comma, try covering it up and rereading your sentence. Does it make sense still?
If so, it needs to be off set with commas.
In a date, set off the year when it’s used with both the month and the day. Don’t use a comma if only the month and year are given.
Rule 12 Example
The ship struck an iceberg on April 14,
1912, and sank early the next morning.
Set off the name of a state or a country when it’s used after the name of a city. Set off the name of a city when it’s used after a street address. Don’t use a comma after the state if it’s followed by a ZIP code.
Rule 13 Example
The ship was sailing from Southampton,
England, to New York
Set off an abbreviated title or degree following a person’s name.
Rule 14 Example
Michelle Nakamura, Ph.
D., will be the graduation speaker.
Set off too when it’s used in the middle of a sentence and means “also.” Don’t set of too at the end of a sentence.
Rule 15 Example
Parents, too, will attend the ceremony.
Rule 16 Example
Mom asked, “Have you finished your homework?”
Use a comma after the salutation of a friendly letter and after the closing of both a friendly letter and a business letter.
Rule 17 Example
I am so glad you came to visit. Please come back soon.
Rule 18 Example
Instead of two, five teachers made the trip.