One of the most common punctuation errors in student writing that I see pertains to comma usage. Too many commas or not enough commas…both are a problem. And it tells me that most people simply don’t know where to put their commas! They are just thrown in willy-nilly with no rhyme of reason, or they are thrown away with reckless abandon. Let’s see if we can clear up the top ten comma rules once and for all.
10. Dates & Addresses:
Place a comma between cities and states or cities and countries; place a comma between the day and year in a date.
London, England January 12, 2016
For large numbers, starting at the decimal, count left and place a comma after each three numbers.
5, 567, 543
Place a comma between the line of dialogue and the tag which tells who is speaking.
Mary said, “Pass me the sugar.”
7. Direct Address & Interjections:
Place a comma after the name that you are speaking directly to as well as after words that indicate exclamation or emotion.
Direct address: Mary, bring me the bread.
Interjection: Wow, I love chocolate!
6. Between Adjectives:
Place a comma between adjectives that are side by side and used to describe the same noun.
I live in a big, blue house.
Place a comma around the noun or noun phrase that explains another noun beside it.
The mosquito, an insect, leaves red bumps that itch.
4. Conjunctive Adverbs:
Place a comma after a conjunctive adverb used to join two main clauses.
I love the holidays; however, I often work too hard.
3. Introductory Elements:
Place a comma after introductory phrases, clauses, and words that appear before the main clause of a sentence.
After breakfast, I leave for school.
2. In Lists:
When writing a list of three or more items, place a comma after each item.
I like pizza, pasta, and garlic bread.
1. Compound Sentences:
Place a comma before the conjunction that joins two independent clauses in a compound sentence.
Harry hit the ball, but John caught it.