In grammar, a clause is a group of words that contains both a subject and a verb. In some cases, a clause can stand alone as a complete sentence; however, a clause does not always express a complete thought.
Your writing, at its best
Compose bold, clear, mistake-free, writing with Grammarly's AI-powered writing assistant
At its most stripped-down, a clause can be two words:
I do.
He walks.
She jumps.
Clauses can be longer, too:
When the languorous night falls on the mountains…
The bowling team, half of the yoga instructors, and the high school kids ate lunch.
After the emaciated tigers tried to escape…
In the examples above, some of the clauses form complete sentences, whereas others do not. Here’s the commonality: every clause contains a subject and a predicate.
To form a complete sentence, you always need at least one main clause.
What Is the Definition of Clause?
In terms of grammar, Merriam-Webster defines the word “clause” as a group of words containing a subject and predicate and functioning as a member of a complex or compound sentence.
In contrast, the definition given by Cambridge Dictionary does not require a clause to be part of a complex or compound sentence. Dictionary.com also omits that requirement.
If she isn’t going to do it, I will.
In the sentence above, grammar enthusiasts would agree that “I will” serves as the main clause because it can stand alone as a complete sentence. However, when we use the same words to form a simple sentence, the dictionaries offer different perspectives.
I will.
According to Merriam Webster’s definition, the previous sentence is not a clause because clauses only appear in complex-compound sentences. The other dictionaries disagree. Based on their definitions, “I will” does qualify as a clause.
How Do Clauses Function?
Many types of clauses exist. The two most important categories are dependent and independent. Dependent clauses do not operate as separate sentences. Instead, a dependent clause functions as a sentence fragment. It must be joined to an independent clause, or main clause, in order to form a complete thought.
Independent Clauses
Independent clauses make complete sense on their own. They can be long or short. In fact, the main clause can be quite long in some sentences. It always contains the most essential information in the sentence.
Some sentences contain more than one independent clause, joined together by a coordinating conjunction, an independent marker word, or a semicolon.
The following words act as coordinating conjunctions or independent marker words. With the help of commas, they can join two independent clauses:
For
And
Nor
But
Or
Yet
So
Also
Consequently
Furthermore
However
Moreover
Nevertheless
Therefore
Avoid comma splices, which occur when you join two independent clauses together in a single sentence without a coordinating conjunction or an independent marker word. If you don’t include one of the words above, use a semicolon to combine two independent clauses.
In complex sentences, finding the main clause may require some skill. To better recognize independent clauses within a complex sentence, learn to identify and eliminate dependent clauses.
Subordinate Clauses
Subordinate clauses, or dependent clauses, cannot stand alone. There are different types of dependent clauses, including adverbial, adjectival, nominal, and conditional.
Adverbial and Conditional Clauses
An adverbial clause is a type of dependent clause that begins with a subordinating conjunction. There are many to choose from, and common subordinating conjunctions include:
Though
While
Till
After
That
If
All adverb clauses answer a question, such as where, why, how, when, or to what degree? Like a typical adverb, these phrases act as modifiers.
Here are a few examples of adverbial clauses:
Since my mom started skiing
Once the lawyers offer council
Before you take the photograph
Clauses that begin with a conditional dependent marker word (if or unless) have a special name: conditional clauses. They’re used to indicate a conditional relationship.
If you loan me a pen
Unless he takes a nap
If a wise man said it
Adjectival or Relative Clauses
Adjectival clauses contain relative pronouns (that, which, who, whom, and whose). For this reason, adjective clauses are also known as relative clauses.
Examples include:
That you mentioned
Who didn’t answer
Which I talked about yesterday
Relative clauses can be either restrictive or nonrestrictive, depending on whether the information they add is essential to the sentence.
I lifted the arm that was broken.
The relative clause above is restrictive because it is crucial to the meaning of the sentence.
The light, which hung above our heads for several years, was bright.
The adjective phrase “which hung above our heads for several years” is set off by commas and could be removed from the sentence without changing much, so it operates as a non-restrictive clause.
Nominal Clauses
A nominal clause functions as a noun, signaling a person, place, thing, or idea. Noun clauses often begin with interrogative words (who, why, whatever, etc.), but they can also begin with expletives (that, if, whether).
I never mentioned why I asked.
I don’t know where he came from.
The question is if we are better off.
In the sentences above, each dependent noun clause acts as the object of the sentence. Since the beginning of each sentence houses the subject of the sentence and the verb, that portion of the sentence constitutes the main clause.
Clauses in Context
In the following sentences, taken from contemporary news articles, we’ve bolded the independent clauses.
I’m an award-winning playwright with a penchant for wordplay. After earning a perfect score on the Writing SAT, I worked my way through Brown University by moonlighting as a Kaplan Test Prep tutor. I received a BA with honors in Literary Arts (Playwriting)—which gave me the opportunity to study under Pulitzer Prize-winner Paula Vogel. In my previous roles as new media producer with Rosetta Stone, director of marketing for global ventures with The Juilliard School, and vice president of digital strategy with Up & Coming Media, I helped develop the voice for international brands. From my home office in Maui, Hawaii, I currently work on freelance and ghostwriting projects.