1. Using Commas Correctly

2. Use commas to …
Punctuate and join parts of sentences
Punctuate names, locations, dates, abbreviations, quotations, and numbers

3. Do not…
use a comma because it sounds as though it should be there.
use a comma just because a sentence is long.
use a comma before every and.
Use a comma between two independent clauses (this is a comma splice!).

4. Use commas between items in a series (three or more words, phrases, or clauses)
We enjoy wine, cheese, and fresh bread.
We are going to fly to Paris, take the train to Italy, and then drive back.

5. Use a comma between two adjectives when and is omitted but could be inserted.
A cold, dark night descended.
They gazed at the deep, frigid snow.
Many elderly people struggled to stay warm.

6. Mary mailed out all the invitations, but she forgot the stamps.
Use a comma before and, but, nor, for, or, so, and yet (fanboys)when joining independent clauses.
Mary mailed out all the invitations, but she forgot the stamps.
Mary mailed out all the invitations but forgot the stamps.
EXCEPT when the two independent clauses are short (less than 10 words) and joined by and or or
George went and I didn’t.
Call me at home or send me .

7. Use a comma after an INTRODUCTORY EXPRESSION
Some examples…
Very short introductory phrases:
Once inside, the man rented skis.
For now, longer skis can be rented.
Introductory expressions using yes, no,well, or oh:
Yes, I expect to go skiing.
Well, I suppose I can take your place.

8. Introductory expressions using a name:
Introductory expressions that include a verb:
When you are ready to ski, call me.
If you are going to come, don’t be late.
Introductory expressions using a name:
Mr. Smith, are you going with us?
After dependent Clauses:
To save both fuel and time, we’ll go together.

9. EXCEPTION:
Commas are NOT required after short place and time introductions, unless a comma would add clarity or emphasis.
In Aspen the snow is perfect for skiing.
Within three hours we should arrive.

10. Use a comma before a sharply contrasting or opposing expression.
These often begin with such words as but, seldom, never, not or yet.
Most scientists support the theory of global warming, but not all.
We open the store at 10 a.m., never before.

11. Use commas to set off nonessential expressions:
We hope, with all sincerity, that you can come.
We understand, however, if you cannot.
Or when renaming a noun (this is called an appositive):
Jim O’Doule, a noted expert, will attend.
Jim, who is a brilliant person, was voted class president.
The insect, a cockroach, is crawling across the kitchen table.

12. I ski in Aspen, Colorado, every year.
Use commas:
To separate city/state or province/ country names:
Dover, Massachusetts
Vancouver, BC, Canada
To enclose names of a state, province, or country in the middle of a sentence.
I ski in Aspen, Colorado, every year.

13. Barbara Cohen, President
Use commas:
After a personal name followed by a professional degree or title:
Winston Lewis, DDS
Barbara Cohen, President
To enclose a title after a name in the middle of a sentence.
Bill Adams, Department Chair, and Tom Abdul, PhD, Professor of Economics, will speak.

14. Use commas in mid-sentence:
To enclose a person’s name.
We hope, Mr. Chow, that you will go with us.
To enclose the year in a date.
On May 4, 1970, we opened our first store.
To enclose a reference to a date.
At 9 a.m., Tuesday, May 4, the service will begin.

15. Use commas with quotation marks:
May asked, “Do you like to ski?”
“I love to ski,” May said.
“One thing I know,” May said, “is that I love to ski.”
May said, “I love to ski,” and then she fell.

16. Do not use a comma before a quotation that blends into the rest of the sentence.
The protestors urged politicians to “clean the air now” during the march.

17. Use commas with numbers that have more than four digits (thousands are optional) :
$10,000
$1,000,000

18. Do not use commas: In street addresses: 16253 Happiness Way
In reference numbers: Invoice no
Between the Province and Postal code: Halifax, NS B3M 1N9
With only the month and year: May 1970
In international date style: 4 May 1970