Commas—How to Use Them

Commas!

Use a Comma after Introductory Word, Phrase, or Dependent Clause

Introductory words at the beginning of a sentence call for a comma to set them off from the root of the sentence. Common introductory words include:

  • However,
  • Still, 
  • Furthermore, 
  • Meanwhile,
  • First,
  • Secondly,
  • Generally, 
  • Suddenly, 
  • Clearly,
  • Quickly,
  • Unfortunately,
  • Afterwards

The coaches reviewed the game strategy. Meanwhile, the athletes trained on the Nautilus equipment. 

Most of the evidence seemed convincing. Still, the credibility of some witnesses was in question.

First, you need to put your name on the paper.

Introductory phrases at the beginning of a sentence also require a comma to set them off from the root of the sentence. A phrase is a group of related words without a subject and a verb. A phrase cannot stand alone; its function is to set the scene for the root of the sentence. 

After breakfast, I went to my English class.

A popular and well respected teacher, Jerry Barnes is a clear favorite to win the award.

The snow blowing violently, the students began to hope for a snow day.

Dependent clauses at the beginning of a sentence also require a comma to set them off from the root of the sentence. A dependent clause is a group of words that contains a subject and verb but does not express a complete thought. Like a phrase, dependent clauses depend on the root of the sentence to make sense and cannot stand alone.

After I ate breakfast, I went to my English class.

Because Jerry Barnes is a popular and well respected teacher, he is a clear favorite to win the award.

Once the snow started blowing violently, the students began to hope for a snow day.

If you use one of these words at the beginning of your sentence, there is a good chance you are starting your sentence with a phrase or a dependent clause that calls for a comma at the end.

  • After . . .
  • Although . . .
  • As . . .
  • Because . . . 
  • Before   . . .
  • Even . . .
  • If . . .
  • Once . . .
  • Only . . .
  • Since . . .
  • Though . . .
  • Unless . . .
  • Until . . .
  • Whatever . . .
  • When . . .
  • Whenever . . . 
  • Whether . . . 
  • While . . .

NOTE: If a phrase or dependent clause comes at the end of a sentence, no comma is necessary.

I went to my English class after I ate breakfast.

He is a clear favorite to win the award because he is a popular and well respected teacher.

The students hoped for a snow day once the snow started blowing violently. 

Use a Comma When Combining Independent Clauses with a Conjunction

An independent clause has a subject and a verb, and it could stand alone as a complete sentence. One way to combine two independent clauses is to use one of the seven coordinating conjunctions preceded by a comma. Using one of these conjunctions will help you avoid a common sentence-joining error known as a comma splice. The seven coordinating conjunctions can be easily memorized by remembering the term FANBOYS.  

_Independent clause                            , for ______independent clause_____________.

, and

  , nor

  , but

  , or

, yet

  , s

To check to see whether you need to use a comma and a coordinating conjunction, make sure that you are combining two independent clauses that are complete sentences in their own right. Each of the underlined clauses below could be a complete sentence on its own, but the writer has chosen to combine them in a single sentence—with the use of a conjunction so as to avoid a comma-splice error.

Examples:

This next chapter has a lot of difficult information in it, so you should start studying right away.

Many companies make sugar-free soft drinks, and the drinks usually contain only one or two calories per serving.

Mr. Leyland played the viola professionally for many years, but he now conducts a community orchestra.

As I turned around, I heard a loud thump, for the cat had upset the goldfish bowl.

Perhaps the artist preferred to paint in oils, or maybe he did not like watercolors.

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