Comma

A comma in writing is like a pause inside a sentence when speaking. We use commas inside sentences. Commas separate parts of a sentence into logical elements. Commas have no meaning, but they help us to see the structure and therefore the meaning of the sentence.

Put a space after a comma. Do not put a space before a comma.

1. Use a comma between items in a series or list. In a sentence, the last two items usually do not need a comma between them as they are separated by "and". However, if one or both of the last two items are long, a comma may be useful.

• coffee, tea, sugar, milk, eggs, butter, salt
• My favourite sports are football, rugby, swimming, boxing and golf.
• Hunsa was wearing blue jeans, black shoes, his brand new white shirt, and a brown and green cap.

2. Use a comma between three or more adjectives or adverbs.

• I like the old, brown, wooden table.
• He bought an old, red, open-top Volkswagen.
• He ran quickly, quietly and effortlessly.

3. For two adjectives, use a comma where you could use "and".

• It was a short, simple film. (It was a short and simple film.)
• I have a big black dog. (I have a big and black dog.)

4. Use a comma for numbers over 999. (In English, commas separate thousands and periods separate decimals. Note that some languages use the opposite system.)

• 1,000 (one thousand)
• 1,569
• $73,050.75
• 2,000,000
• 3,400,500
• 10.5 (ten point five or ten and a half) - note the use of the period, not comma

5. Use a comma for addresses, some dates, and titles following a name.

• 911 Avenue Mansion, Sathorn Road, Bangkok 10100, Thailand
• Los Angeles, California
• November 4, 1948 (but 4 November 1948)
• Fred Ling, Professor of English

6. Use a comma before or after direct speech. Do not use a comma for reported speech.

• He said, "I love you."
• "I love you," he said.
• He told her that he loved her.

7. Use a comma before a coordinating conjunction (for, and, nor, but, or, yet, so) to join two independent clauses. If the independent clauses are short and well-balanced, a comma is optional.

• He didn't want to go, but he went anyway.
• I want to work as an interpreter, so I am studying Russian at university.
• She is kind so she helps people.

8. Use commas for parenthetical elements. A "parenthetical element" is any part of a sentence that can be removed without changing the real meaning of the sentence.

• John Geton, who is chairman of the company, is quite old.
• Andrew, my wife's brother, cannot come.
• Andrew (my wife's brother) cannot come.
• The objective, to find peace in both countries, is hard to reach.

9. Use a comma after an introductory element. A comma is optional for short, simple introductory elements.

• Rushing to catch the flight, he forgot to take his phone.
• As the year came to an end, he realised the days were getting shorter.
• By evening we were getting worried.
• After a hefty meal cooked by his host's wife, he went to sleep.
• After a snack he went to sleep.

10. Sentence adverbs (words like however, unfortunately, surprisingly that modify a whole sentence) often require one or two commas, depending on their position in the sentence.

• However, Anthony did arrive.
• Anthony, however, did arrive.
• We were, unfortunately, too late.
• He had, not surprisingly, lost his temper.

11. An adverbial clause often needs a comma when it comes at the beginning of a sentence (but not at the end of a sentence).

• If I win the lottery, I will buy a castle.
• I will buy a castle if I win the lottery.

12. Do not use a comma to separate two complete sentences. In this case, use a full stop (period) or semi-colon.

• Ram wants to go out. Anthony wants to stay home.
• Ram wants to go out, Anthony wants to stay home.

I have spent most of the day putting in a comma and the rest of the day taking it out. Oscar Wilde