Clauses in English: Independent, Dependent, Relative, and More

A clause is a group of words containing a subject and a verb. Clauses are the building blocks of sentences. Understanding the different types of clauses will help you write more complex and varied sentences.

Independent Clauses

An independent clause can stand alone as a complete sentence. It expresses a complete thought and contains a subject and a verb.

She writes every day.

The sun set over the mountains.

Independent clauses can be joined with coordinating conjunctions (for, and, nor, but, or, yet, so) to form compound sentences.

She writes every day, and she publishes weekly.

Dependent Clauses

A dependent clause contains a subject and a verb but cannot stand alone. It needs an independent clause to complete its meaning. Dependent clauses begin with subordinating conjunctions (because, although, when, if, while, since, unless) or relative pronouns (who, whom, which, that, whose).

Because she studied hard, she passed the exam.

I will call you when I arrive.

If a dependent clause comes before the independent clause, use a comma. If it comes after, no comma is needed.

Relative Clauses

Relative clauses give more information about a noun. They begin with relative pronouns: who, whom, which, that, whose. There are two types: defining and non-defining.

Defining Relative Clauses

A defining relative clause gives essential information about the noun. Without it, the sentence meaning changes. Do not use commas.

The woman who lives next door is a doctor.

The book that I borrowed is excellent.

In defining clauses, that can replace who or which in everyday English. The object pronoun can also be omitted: The book I borrowed (no relative pronoun needed).

Non-Defining Relative Clauses

A non-defining relative clause adds extra, non-essential information. Use commas and never use that — only who or which.

My sister, who lives in London, is visiting us.

The Eiffel Tower, which is in Paris, is beautiful.

Noun Clauses

A noun clause functions as a noun in a sentence. It can be a subject, object, or complement. Noun clauses begin with words like what, that, whether, if, who, why, how, whatever, whoever.

What she said surprised everyone. (subject)

I know that she is right. (object)

That is what I meant. (complement)

Noun clauses are often introduced by that after verbs like think, believe, know, say, hope, and feel. In informal English, that can be omitted: I think she is right.

Adverbial Clauses

An adverbial clause modifies the verb in the independent clause. It tells when, where, why, how, or under what conditions something happens. They begin with subordinating conjunctions.

Time: Call me when you arrive. (when, while, before, after, until, as soon as)

Place: Put it where you found it. (where, wherever)

Reason: He left because he was tired. (because, since, as)

Purpose: She saved money so that she could travel. (so that, in order that)

Concession: Although it rained, we enjoyed the trip. (although, though, even though)

Condition: If it rains, stay home. (if, unless, provided that)

Manner: Do it as I showed you. (as, as if, as though)

Sentence Types by Clause Structure

Understanding clauses helps you identify sentence types. A simple sentence has one independent clause. A compound sentence has two or more independent clauses joined by coordinating conjunctions. A complex sentence has one independent clause and at least one dependent clause. A compound-complex sentence has at least two independent clauses and at least one dependent clause.

Analyze Your Sentence Structure

Using a variety of clauses makes your writing more engaging. Use our free sentence counter to analyze your sentence types and ensure you have a good mix of simple, compound, and complex sentences.

Frequently Asked Questions

What is the difference between a clause and a phrase?

A clause contains a subject and a verb, while a phrase does not. "Running fast" is a phrase; "She runs fast" is a clause.

Can a dependent clause be a sentence?

No. A dependent clause cannot stand alone. "Because I was tired" is a sentence fragment. It needs an independent clause to form a complete sentence.

What is a relative clause?

A relative clause gives information about a noun and begins with a relative pronoun like who, which, or that. Example: "The car that I bought is red."

When do I use which vs that in clauses?

Use that for defining clauses (essential information). Use which for non-defining clauses (extra information, with commas). In defining clauses, both are acceptable in informal English.

What is a noun clause?

A noun clause acts as a noun in a sentence. It can be a subject: "What you said is true." Or an object: "I know where she lives."