Comma Rules

Rules for Commas:

1) They divide items in lists, but are not require before the “and” on the end.

Example:  The four refreshing fruit flavors of Opal Fruits are orange, lemon, strawberry and lime.

The rule here is that the comma is correct if it can be replaced by the word “and” or “or”.

Example: The four refreshing fruit flavors of Opal Fruits are orange and lemon and strawberry and lime.

Note: It is not incorrect to put a comma before the “and” at the end.

Example: The four refreshing fruit flavors of Opal Fruits are orange, lemon, strawberry, and lime.

2) Commas are used when two complete sentences are joined together using such conjunctions as “and”, “or”, “but”, “while”, and “yet”. 

The boys wanted to stay up past midnight, but they had a race to run the next day, and their coach told them “no”.

Note: A comma splice occurs when you use a comma when a semi-colon is called for.

Example: It was the Queen’s birthday on Saturday, she received a lot of presents.

It should be written: It was the Queen’s birthday on Saturday; she received a lot of presents. 

Or: It was the Queen’s birthday on Saturday, and she received a lot of presents.

3) Commas fill gaps where other words might go.

Example:  Annie had dark hair; Sally, fair.

4) Commas before direct speech.

The queen said, “It’s my birthday and I want lots of presents.”

Note: Many authors use colons: these days.  Joyce used dashes –. 

5) Commas set off interjections.

Stop, or I’ll scream.

6) Commas set aside non-essential information.

John Keats, who never did any harm to anyone, is often invoked by grammarians.