How to use commas

How to use commas

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Commas are used to separate list items.

1. When there are more than two items in a list, they should be separated using commas. The last item is usually preceded with "and", "or" or "but". (These are called "conjunctions".) There is normally no need to put a comma before the conjunction.

Examples:

The old vicar, the new vicar, the pub landlord, the mayor and the chairman
were at the meeting.

(no comma before "and")

I have not seen any foxes, badgers or deer in these woods this year.

(no comma before "or")

2. However, on occasion, it is appropriate to place a comma before the conjunction in order to avoid any ambiguity.

Examples:

The news will be shown after Dangermouse, and Rug Rats.

(Without the comma, readers could think that "Dangermouse and Rug Rats"
is one programme.)

The emblem is an amalgamation of the British and Irish flags, the Stars
and Stripes, and the Hammer and Sickle.

(The word "and" appears lots of times in this example. The comma before
the "and" makes it easier for the reader.)

I need to see DC Jones, PC Pinner, and PC Hoyles in my office immediately.

(no ambiguity - comma not required)

She went to the shops for eggs, milk, and butter. ^{(Mini Test)}

BEWARE CONFUSION WITH AN EXTRA COMMA

As covered in Section 4 below, commas can also be used to introduce additional information (called parenthesis). For example:

My friend, Simon, lives near the concrete cows in Milton Keynes.
(In this example, commas are being used to add information
about "my friend".)

Therefore, if a comma is used unnecessarily before a conjunction in a list, it could look like parenthesis and cause confusion. For example:

I left the pub with my friend, Simon, and Terry.
(In this sentence, I left the pub with two people: Simon and Terry.)

I left the pub with my friend, Simon and Terry.
(In this sentence, I left the pub with three people: my unnamed
friend, Simon and Terry.)

This is why you should avoid using a comma before the conjunction in a list.

3. Often in creative writing, there is a need to use several adjectives (describing words - see lesson "Adjectives"). A list of adjectives is governed by rules that are slightly different (more relaxed):

For TWO adjectives
vast, inhospitable moor (with a comma)
vast and inhospitable moor (with "and")
vast inhospitable moor (with nothing)

For THREE or more adjectives
vast, inhospitable, windy moor (commas between)
vast, inhospitable and windy moor (comma(s) between and then "and")
vast inhospitable windy moor (nothing between)
vast inhospitable and windy moor (nothing and then "and")

CONFUSED?

There is no need to worry. In short, you cannot go wrong with 2 adjectives and using 3 is rare. (Lining up adjectives in a row is called "enumeration of adjectives".)

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A comma is used after an introduction to a sentence.

1. It is common for a sentence to start with an introduction. An introduction can be anything from just one word to a long clause. In general, an introduction is used to state a time, a place, a condition, a frequency or a fact before the main part of the sentence. (Introductions vary hugely.)

Examples:
In the centre of London, the number of people who fell victim to pickpockets
       rose by 30 per cent in a month. (sets a place)
As soon as the cake is golden-brown, take it out of the oven. (sets a time)
Yesterday, the manager visited the stables. (sets a time)
On Tuesday 4th July a band played carols in the park for 8 hours.
       ("On Tuesday 4th July" sets a time. It is an introduction and should be
       followed by a comma.)
Having spoken to John, I can confirm that the meeting is definitely off.
      (states a fact)
As you are well aware, the latest figures do not look promising.
      (states a fact)
After the secretary had read the minutes of the meeting, the chairman
       asked for the financial report. ^{(Mini Test)}

ONLY USE A COMMA FOR AN INTRODUCTION

Words that "set the scene" do not always start the sentence; they could appear at the back or in the middle. You only need a comma when these words appear at the front of the sentence. This is very handy to know. Look the examples below:

At 4 o'clock, the new manager, David Bain, will visit.
(correct, but too many commas)

The new manager, David Bain, will visit at 4 o'clock.
(correct - much tidier)

A band played in the park for 8 hours on Tuesday 4th July. ^{(Mini Test)}

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A comma is used after an introduction that links the sentence to the previous one.

1. It is common for a sentence to start with an introduction that acts like a bridge between the last sentence and the new sentence. The introduction makes the transition between the two sentences smoother. (It is known as a "transitional phrase".) It always appears at the start of a sentence and is followed by a comma. (This subject is closely related to Section 2 above.)

Examples:

Bruce Leonard spent 4 years in Japan studying Kung Fu and 3 years at the
London School of Martial Arts as the senior instructor. As a result, his style...

("As a result" is a transitional phrase. It acts like a bridge between the previous
sentence and the new one. It is followed by a comma.)

Of course, he never knew…

("Of course," < transitional phrase)

In summary, 7 out of 10…

("In summary," < transitional phrase)

Therefore, the cost of each lesson…

("Therefore," < transitional phrase)

Consequently, his teaching techniques…

("Consequently," < transitional phrase)

However, Bruce was unaware…

("However," < transitional phrase)

SEMICOLONS

On occasion, you may wish to use a semicolon before a transitional phrase to make the transition between sentences even more seamless. (This is covered in lesson "Semicolons".)

I cannot come on Tuesday. However, Peter will be there.

(However - transitional phrase)

I cannot come on Tuesday; however, Peter will be there.

(however - transitional phrase using a semicolon)

NOT A COMMA

You cannot use a comma before a transitional phrase.

I cannot come on Tuesday, however, Peter will be there.

This is a very common error.

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Commas can be used for parenthesis.
(also covered in lesson "Parenthesis")

PARENTHESIS?

A parenthesis is additional information in a sentence. If a parenthesis is removed, the sentence still makes sense.

The defendant, Mr Michael Evans, sat in silence.

("Mr Michael Evans" is additional information. This is
a parenthesis.)

The last owner of the Red Lion, who is my sister's neighbour,
won over 4 million on The National Lottery.

("who is my sister's neighbour" is additional information. This is
a parenthesis.)

Comments such as "however", "therefore", "as a result", "as far as I am concerned", etc. fall into the category of parenthesis too.

John Winfield, on the other hand, is an exprienced jockey.

1. Commas can be used to separate a parenthesis from the rest of the sentence. It is also possible to use dashes or brackets. When used in this way, commas, dashes and brackets are called "parentheses". (See lesson "Parenthesis" for more information.)

Examples:

The second boat in the race, the 6-berth Kontarka, was crewed by school
children from Pembrokeshire.

Last year's GB faggot-eating champion who works with my brother came
in here and ate two loaves of bread in one sitting. ^{(Mini Test)}

2. Although the use of commas for parentheses makes for a normal-looking sentence, they can become confused with other commas in the sentence.

Example:

Last night, Josie, an escaped wallaby from London Zoo, attacked two young
sisters, Rebecca and Josie, which is pure coincidence, Evans, in a bid to steal
their crisps.

(Although grammatically correct, the writer could have used a mixture of
parentheses in order to make the sentence clearer.)

Last night, Josie (an escaped wallaby from London Zoo) attacked two young
sisters - Rebecca and Josie (which is pure coincidence) Evans - in a bid to steal
their crisps.

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A comma can be used before words like "and", "or" and "but" (also covered in lesson "Conjunctions").

1. Words like "and", "or" and "but" are known as "conjunctions". (There are other conjunctions, but these 3 are by far the most common. For more information, see the lesson "Conjunctions".) As well as being used in a list, a conjunction can be used to merge two sentences into one. This is very common. When a conjunction is used in this way, it should have a comma before it. (It is called a "co-ordinate conjunction" in this role.)

Examples:

He is a great swimmer, but he prefers to play golf.

("He is a great swimmer." + "He prefers to play golf.")
(This is two sentences merged into one with "but" - comma required.)

	[picture]

I may consider your plan, or I may disregard it.

("I may consider your plan" + "I may disregard it." - comma required)

The female applicant must be able to tell jokes and sing, and she must be
able to dance.

("The female applicant must be able to tell jokes and sing." + "She must be
able to dance." - comma required)

The female applicant must be able to tell jokes, sing, and dance.

(normal conjunction - no comma required)

PLC provided the material, and we built the road. ^{(Mini Test)}

TOO MANY COMMAS

When sentences containing commas are merged together using a conjunction, it is possible to use a semicolon instead of a comma. (See lesson "Semicolons" for more examples.)

Last year, PLC provided the material; and we, L&S Ltd, built the
road.

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A comma is used after an introductory expression such as "yes", "indeed" and "absolutely".

1. Expressions such as "yes", "no" and "indeed" are used as "interjections". (See lesson "Interjections" for more information.) Interjections can be followed by a comma.

Examples:

Well, the rain has played its part in the outcome of this match.

Yes, she will apologise.

Absolutely, a fifth of all the students live in the village.

MILDER WITH A COMMA

An interjection can also be followed by an exclamation mark, but this gives the interjection more impact. (Consider the difference between "No!" and "No,".)

USUALLY NOT IN BUSINESS WRITING

Interjections are usually only used when spoken words are being quoted. You should avoid them in business writing.

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A comma can be used before a quotation.
(also covered in lesson "Quotation Marks")

1. A comma can be used before a quotation after words like "He said", "She whispered", "It stated", etc.

Examples:

The janitor said, "That's me in the '60s."

Bessie stretched across my plate and grunted, "salt...salt and pepper".

The sign states, "Animals drive very slowly".

COMMAS FOR SHORT QUOTATIONS

There are guidelines (fast becoming outdated) which state that only a quotation of six words or fewer should be introduced with a comma. Longer quotations should be introduced with a colon. For example:

The janitor said: "See the long-haired one? That's me in the '60s."

(This is covered more in the lesson "Quotation Marks.")

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Commas are used with large numbers to separate the thousands (i.e. every 3 decimal places).

1. Commas can be used to make reading numbers a little easier. They are placed every 3 decimal places for numbers comprising 4 digits or more.

Examples:

1,234

23,566

1,234,967

Serial number 1654880 was destroyed in 1984.

(not in reference numbers or years)

2. On the continent, the use of commas and full stops in numbers is reversed.
4,567.1 (British version)
4.567,1 (European version)

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Commas are used to show the vocative case.
(also covered in lesson "Vocative Case")

VOCATIVE CASE?

When somebody is being addressed directly, his/her name must be separated from the rest of the sentence with a comma (or commas). (Names that are being addressed directly are said to be in the "vocative case".)

1. Separate names being addressed from rest of the sentence using a comma or commas.

Examples:

Alan, put your hand up if you do not understand.

("Alan" is being addressed. The word "Alan" is said to be in the "vocative
case". It must separated from the rest of the sentence with a comma.)

Where do you think you are going, you little devil?

(Somebody is being addressed as "you little devil". Those words are in the
vocative case, and a comma is required.)

Absolutely, John, get your skates on. ^{(Mini Test)}

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A comma can be used to group a long subject (explained below).

SUBJECT?

The subject of a sentence is the person or thing that is performing the verb in the sentence. (Verbs are doing words like "to dance" and " to sit" - see lesson "Verbs".)

Balloons rose out of the stadium.
(The word "Balloons" is the subject of this sentence. They are
performing the verb; in this case, the verb "to rise".)

David Baker is a real gentleman.
("David Baker" is the subject of this sentence. He is performing
the verb; in this case, it is the verb "to be".)

The man next door saw that stray dog again.
("The man next door" - subject / "to see" - the verb)

Jack and Simon are in the swimming pool.
("Jack and Simon" - subject / "to be" - the verb)

1. As in the last example above, the subject of a sentence can consist of more than one person or thing. (This is known as a "compound subject".) Sometimes, the subject is made up of so many elements that writers like to end the list with a comma to group them together.

Example:
A clean driving licence, the ability to operate under pressure and 5 years'
       experience in marketing, are the only criteria stipulated by the selection panel.
      ("A clean driving licence, the ability to operate under pressure and 5 years'
      experience in marketing" is the compound subject of this sentence. The verb is
      "are" - from the verb "to be".)

FROWNED UPON?

Be aware that ending a long compound subject with a comma is not popular with some grammarians. It is not wrong, but is best avoided.

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