Comma Rules

Comma Rules

The comma is one of the most common – and most often misused – marks of punctuation. And why is that? 

It seems so very simple – and you can be seen as an excellent writer if you learn the comma rules and use them accurately.

First, the comma is a pause only – not a full stop, as we can describe the period.  It’s only a partial stop – a slight pause – where you would take a breath if you were reading.  

The comma is an important mark of punctuation, particularly when someone is reading aloud -  so that you and your listeners can understand the meaning clearly.

Learning to read aloud clearly is another skill that one can learn – and in so doing, one will realize just how important these marks of punctuation truly are!

So, let’s look at a few Comma Rules and a few examples so that you can learn to use the comma properly.  But first, you need a few definitions:

  • Phrase.  A phrase is a group of words that has no verb.
  • Clause.  A clause is a group of words that includes a subject and verb.  It can stand alone, as an independent clause or not stand alone, as a dependent clause. 

Nevertheless, if you begin a sentence with a clause, or a phrase, or a word, you must add a comma after it.




A few common comma rules

Comma Rules

Place a comma after an introductory word, phrase, or clause.  

Introductory word

  • However, I guess I have to show you the examples.
  • Nevertheless, I will find examples to show you.


Introductory phrase

  • In the evening, we like to watch television.
  • In the morning, I like to get up early and go for a long walk.


Introductory clause

  • When we come home from work, we like to enjoy a quiet time before supper.
  • When we sit quietly and listen, we hear all manner of inspiring activity around us.


Misuse of the comma


Often, the comma is misused because it is added at the end of a sentence.  Instead, you need a period (a “full stop”) at the end of the sentence. 

When you place a comma at the end of a sentence, and then keep going – that is called a comma splice.  Click here for more information on the comma splice.


Words/phrases in a series

Place a comma after each word in a series.  

  • We bought eggs, bacon, and bread at the grocery store.

(There is a controversy about the final comma.  Some would omit the final comma before “and.”  As I am a purist, I prefer to include all the commas.)

Place a comma after each item in a series. Perhaps the series is made up of a phrases or similar groups of words.  The comma is placed in the same manner. 

In each of the following, the phrases begin with a verb:

  • We drove to the farm, fed the animals, collected the children, and then returned home.
  • As we chased the dog, he ran round the yard, round the tree, across the road,  and into his dog house.





Comma Rules for Clauses and Phrases

When writing, add commas surrounding the non-essential (non-restrictive) clause or phrase.  When writing, do not add commas around the essential (restrictive) clauses or phrases. 

For the next part, you need a few definitions – so here they are again.

  • Phrase.  A phrase is a group of words that has no verb.
  • Clause.  A clause is a group of words that includes a subject and verb.  It can stand alone, as an independent clause or not stand alone, as a dependent clause. 


Comma Rules - Definitions required

Comma Rules - Definitions required

(a) Restrictive phrases or clauses.  Some phrases or clauses in a sentence are necessary for identification and understanding.  Those phrases or clauses would be “essential” or “defining” or “restrictive.”  All terms mean the same thing.

(b) Non-restrictive phrases or clauses.  Some phrases or clauses in a sentence are not necessary for identification and understanding.  Those phrases or clauses would be “non-essential” or “non-defining” or “non-restrictive.”  All terms means the same thing.

  • When writing, add commas surrounding the non-essential clause or phrase.
  • When writing, do not add commas around the essential clauses or phrases.  


What is the comma?  Learning basic comma rules will be helpful!

The comma is a short pause and adds a great deal of “sense” and understanding to the sentence.

  • The commas surrounding  a phrase in a sentence will cause the reader pause when reading -  so as to indicate that the phrase is one that simply adds non-essential additional information for interest. 
  • It will be very clear that the information is not necessary to the sentence. 
  • If you then look closely at that phrase, you will realize that the sentence makes sense even if you remove the phrase that is surrounded by those commas.


Restrictive/Essential/Defining
For example:

  • The woman in the red dress is my aunt.
  • The house that I live in is at the end of the street.  
  • The book that I read last week was one of the most interesting I’ve ever read!

Each of the italicized phrases and clauses shown above are necessary for meaning in the sentences.

  • It’s not just any woman – it is the woman in the red dress who is my aunt.
  • It’s not just any house – it is the house that I live in that is at the end of the street.
  • It’s not just any book – it is the book that I read last week that is the most interesting.


So, clearly the phrases and clauses are necessary to the meaning of the sentence. There are no commas.  Each one is an essential clause or a restrictive clause or a defining clause.  All terms may be used – and all have the same meaning.

Non-restrictive/Non-essential/Non-defining

However, what if we want to describe the woman, the house, and the book in another way – in a way that is not directly necessary for the identification?  We would then write the optional phrases and clauses using commas.

  • The woman in the red dress, who is a very knowledgeable professor, is my aunt.
  • The woman in the red dress, who has three grown children, is my aunt.

OR

  • The house that I live in, which has two storeys, is at the end of the street
  • The house that I live in, which is a red brick house, is at end of the street.  

OR

  • The book that I read last week, which I picked up at the library, was one of the most interesting I’ve ever read!
  • The book that I read last week, which had 300 pages, was one of the most interesting I’ve ever read.


The commas surround the information that is non-essential to the identification.

Summary

If you use the commas correctly, you can remove the section between the commas and not drastically change the meaning of the sentence.  The information that is surrounded by commas simply adds additional unnecessary – but interesting – information.

If you read the sentence aloud – you will hear the pause at each comma – and you will hear how the commas are necessary - how the commas (the pauses) define the meaning of the sentence.

The commas must be used in pairs in such a case.  Add the comma at the start and at the end of the phrase or clause for an accurate presentation.

If you work diligently, you can learn the Comma Rules and become an excellent and professional writer!  Focus on success!


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