Use commas to separate a list of similar words or phrases:
We adore Emma because she is kind, loving and responsible.
Daisy was more open, more comfortable and more willing to share her feelings with us this time.
A comma isn’t commonly used before “and” at the end of a list of single words:
We visited Vietnam, Malaysia and Singapore this month.
A comma is commonly used in list before “and” in American English:
We brought bread, butter, and jam for everyone.
Commas are used to separate words or phrases that indicate where the one would pause slightly:
James, the math teacher, got married this morning.
They are, in reality, very inconsiderate people.
If the clauses he the same subject, a comma isn’t commonly used when main clauses are separated by and, or, but. However, commas are normally used if the clauses he different subjects:
Danny is teaching English and learning Chinese in China. (same subject)
Doctors make a healthy living but health care reform and efforts to control medical costs are affecting the way they do business. (same subject)
Lydia wants to live in Sydney, but she decided work prospects are better in Melbourne. (different subjects)
When a subordinate clause comes before the main clause, it’s common to use a comma to separate the clauses. However, it’s not always done in short sentences:
If you want to update the company website, please feel free to email or phone me.
If you want the website updated just call us.
when using subordinate or non-finite comment clauses to give further details or more information, it is common to use commas to separate the clauses:
In my honest opinion, their performance was extremely good.
You do need more exercise, if I may say so.
Commas and relative clauses: Commas are used to mark non-defining clauses. Such clauses normally add extra, non-essential information about the noun or noun phrase:
Her aunt, who arrived one hour late, was the first person to get on the dance floor.
Bathurst, the city where I lived throughout my childhood, is home to many of my friends.
Commas are not used to mark defining clauses:
Blackburn is the eastern suburb that has been selected for the Eastern District Junior Basketball tournament.
Commas and speech forms: Normally tags and yes-no responses are separated with commas:
You are attending Joanne’s wedding, aren’t you?
Yes, please. I would love another slice of the cheese cake.
Commas are used to show that direct speech is following or has just occurred:
He declared to everyone, “I am getting married.”
When the direct speech is first, use a comma before the closing of the quotation marks:
“Please make sure this doesn’t happen again,” he said sternly.