Using Commas

What is a Clause?

A clause is a group of words containing a subject and a predicate. Understanding clauses goes hand-in-hand with understanding commas, as commas tend to separate clauses.

What is a Subject? 

A subject is what the sentence is talking about or describing. While often a noun, the subject can be any word or set of words that act like a noun.

What is a Predicate?

A predicate is any description or action of the subject. The section of the sentence that provides information about the subject is the predicate. 

Examples with the subject bolded and predicate in unbolded:

• Jonas gardens with his spade. 

• The gardener’s spade is incredibly sharp.

An independent clause can stand alone as its own sentence. A dependent clause would not make sense by itself.

Example of an independent clause: 

• Jonas gardens with his spade.

Example of a dependent clause: 

• . . . since he loves to watch the flowers bloom.

When the dependent clause comes before the independent clause, a comma is used to separate them:

Examples:

• Since he loves to watch the flowers bloom, Jonas gardens with his spade.

• Given that I enjoy them so much, I think I’ll go on a movie marathon.

This is not true if the independent clause comes before the dependent clause. Let’s flip the above examples around:

• Jonas gardens with his spade since he loves to watch the flowers bloom.

• I think I’ll go on a movie marathon given that I enjoy them so much.

A coordinating conjunction can establish a relationship between independent clauses. When two independent clauses are put together within the same sentence, place a comma and a coordinating conjunction to link them. A comma without the conjunction between independent clauses creates an error called a comma splice.

❌Jonas gardens with his spade, it is incredibly sharp.

✅Jonas gardens with his spade, and it is incredibly sharp.

A parenthetical is a word or phrase that is not grammatically essential but adds context to the sentence. It can be removed from the sentence without changing its intended meaning, and it is not required for the sentence to be a complete thought. However, commas can help to distinguish parenthetical phrases from the rest of the sentence. 

Examples:

• If the air is fresh, I love to go for walks.

• Early in the morning, my favorite things to eat are bacon and eggs.

• As I’ve always wished, I’m going on a trip to the White House.

The above examples each include an introductory phrase that comes before the main sentence, introducing it. However, since these phrases act as “sidenotes” they can often be freely moved within the sentence. Let’s shift these parentheticals to the middle or end of the above examples.

• I love to go for walks, if the air is fresh.

• My favorite things to eat, early in the morning, are bacon and eggs.

• I’m going on a trip to the White House, as I’ve always wished.

To express contrast:

• The work was about passion for him, not money.

• The tools were efficient, but very loud.

When using multiple adjectives: 

When multiple adjectives describe a noun equally, they are called coordinating adjectives. Usually, “and” or “but” can be placed between these or they can be reordered without looking out of place. 

Examples of coordinating multiple adjectives: 

• The bill was an intimidating, hefty sum.

• The stubborn, unscrupulous businessman refused the advice.

When a quote is introduced within a sentence:

• The news said, “there will be a huge meteor shower tonight”!

• I am quick to make judgements, so people tell me, “be careful what you wish for.”

• “Don’t talk to me or my son ever again,” yelled the man.

Don’t use a comma if the quote flows naturally with the text:

• He said that “spiders are cute, not scary.” 

• Manatees are “aquatic mammals also known as sea cows.”

If an independent clause introduces the quote, a colon can be used instead:

• Many individuals are happy about the change: “People are celebrating everywhere.”

To Avoid Confusion:

Confusing: Let’s eat grandma.

Clarified: Let’s eat, grandma.

Confusing: I like the new policy as well as my family likes it.

Clarified: I like the new policy as well, as my family likes it.

To separate elements in a series.

• We went through Maine, New Hampshire, and Massachusetts.

• Do you want a red, yellow, or blue backpack? 

See our tables on the serial comma in our Commas Handout.