Commas, Commas, and more Commas
Chicago Manual Style – Time
You may have heard that it’s optional to put a comma before the word and when listing things. This is called the serial or Oxford comma, and if you are writing using the CMS, you need to include it (CMS 6.18).
I went to the store to pick up bananas, milk, and eggs.
If it is a longer list of complex thoughts, you may want to use a semicolon instead (CMS 6.19)
On vacation, we are thinking about climbing to the top pf the hill for lunch; going to the museum and eating there; or taking a bike ride and stopping by the lake to eat.
When an ampersand is used instead of the word “and,” as in the case of a company name, you leave out the serial comma (CMS 6.21).
He worked for Franklin, Davis & Jones Distributor.
I think I finally figured out a way to remember when to use commas with appositives. An appositive is a word, phrase, abbreviation, or clause that provides an explanatory equivalent. If you need the clause, then you don’t need the commas (CMS 6.23).
Dawn’s husband, Pete, is in the Air Force.
Dawn only has one husband, therefore the descriptor “Pete” is not actually needed.
But if you need the clause for clarification, you don’t need the commas.
Dawn’s book The Obsession is being released in large print.
But the one that REALLY gets me, is when used with the words but or so. Use with an independent clause seems pretty straightforward to me. If there is a subject on both sides of the conjunction, you need a comma (CMS 6.28).
I’m not excited to go back to college, but Rachel is ready.
If it’s a compound predicate, sharing a subject, no comma is needed (CMS 6.29).
She tried to get his attention but was unable to reach him.
For descriptive phrases, I think it’s harder to recognize. Think back to CMS 6.23 when I said if the information is needed, you don’t need the commas. For words like “however,” “therefore,” and “so,” if the clause is essential to the meaning, then you don’t use commas (CMS 6.25).
This will keep your skin looking healthier so there’s no need for expensive makeup.
There are many different rules for commas, so I think we’ll have to address this topic again.