What Are Dependent and Independent Clauses?

Understanding independent and dependent clauses is essential to writing and editing – but how exactly are they different? And how should you punctuate sentences with independent and dependent clauses? We’ve got the answers! Keep reading to learn what makes a clause independent or dependent and how to write both correctly.

What Is a Clause?

A clause is a group of words that contains both a subject and a predicate. For example, Jane ran a mile. Clauses can be long or short, but they always need to have at least one subject and one predicate.

Next, let’s look at independent and dependent clauses and how they’re different. 

Independent Clauses

Independent clauses can stand alone as complete sentences and must contain a subject and a predicate. They can also be part of a compound sentence, which is  made up of two or more independent clauses. If they are part of a compound sentence, then one way to join them is with a coordinating conjunction. For example:

I went to the movies with my sister, and we decided to get some popcorn.

Here, I went to the movies with my sister and we decided to get some popcorn are both independent clauses. They make up a compound sentence, and a coordinating conjunction (and) joins them. Here’s another example:

She sold her house, but she didn’t get the price she wanted.

In this example, the coordinating conjunction but links the two independent clauses (which both have a subject and a predicate).

Punctuating Compound Sentences

FANBOYS is an acronym for the following coordinating conjunctions: for, and, nor, but, or, yet, and so. When we use these to connect two independent clauses, we must place a comma before them. In the examples above, you can see that and and but connect the clauses and are thus preceded by a comma.

Dependent Clauses

A dependent clause contains a subject and a predicate but cannot stand as a complete thought by itself – it adds “extra information” to a sentence. A subordinating conjunction, such as when, that, or unless, usually connects the dependent clause to the sentence’s main clause. If a dependent clause is located at the end of a sentence, you don’t need a comma to link it to the main clause. For instance:

I want to borrow the magazine that Jen read yesterday.

In this example, the dependent clause has a subject (Jen) and a predicate (read) and follows an independent clause (I want to borrow the magazine). Here’s another example:

We’ll start the movie when Kim arrives.

As you can see, the dependent clause following when adds essential information to the sentence but couldn’t stand on its own as a complete thought. Since it follows the independent clause, no comma is necessary. 

However, you do need a comma to link an independent clause with a dependent clause when the dependent clause is located at the beginning of the sentence. For example:

Until summer arrives, we need to keep the heater on.

Note that you do not need a comma if that same dependent clause is located at the end of the sentence:

We need to keep the heater on until summer arrives.

Becoming A Proofreader

If you’re interested in learning more about independent and dependent clauses, as well as many other English grammar terms and rules, consider taking our Becoming A Proofreader course. You’ll learn everything you need to know about grammar, punctuation, spelling, and more. Sign up for a free trial and get started today!