What Is a Subordinate Clause? It’s a dependent clause that needs a main clause to form a complete sentence and express a clear meaning.
Common types of subordinate clauses include time clauses, concessive clauses, and clauses showing place, reason, contrast, or concession.
Words such as although, when, and because can introduce them, while relative pronouns add additional information to improve sentence structure.
What Is a Subordinate Clause?
To begin, a subordinate clause is a group of words containing a subject and a verb that cannot normally stand alone as a complete sentence.
For example, take the following:
Although Sara was tired
This group contains:
- Subject: Sara
- Verb: was
- Subordinating word: although
Even so, it feels unfinished. Naturally, the reader asks, “What happened although Sara was tired?”
Now, complete the sentence:
Although Sara was tired, she finished her work.
Here, the first part is the subordinate clause, while the second part is the independent clause.
In other words, the subordinate clause adds information, but the independent clause carries the main message.
Why Is It Called a Dependent Clause?
Put simply, the terms subordinate clause and dependent clause generally refer to the same grammatical idea.
“Dependent” describes exactly what the clause does: it depends on another clause to function as a complete sentence.
To illustrate, compare these examples:
| Clause | Complete Sentence? |
| She left early. | Yes |
| Because she felt sick. | No |
| Because she felt sick, she left early. | Yes |
Notice how the word because changes the relationship between the ideas. While “She felt sick” can stand independently, “because she felt sick” cannot.
Ultimately, this is one of the easiest ways to understand subordination: the clause has a subject and verb, but something makes it dependent.
The Basic Structure of a Subordinate Clause
Generally speaking, a subordinate clause contains three important elements:
- A subject
- A verb
- A subordinating element
For instance:
When the class ended, the students left.
Here:
- When = subordinating conjunction
- the class = subject
- ended = verb
As a result, the clause when the class ended cannot normally stand by itself.
That said, not every subordinate clause follows exactly the same pattern. Relative clauses, for example, can begin with relative pronouns such as who, which, that, or whose, while noun clauses can begin with words such as what, whether, why, or how.
Subordinate Clause vs. Independent Clause
At its core, the most important distinction is simple:
An independent clause can stand alone. A subordinate clause cannot.
Specifically, an independent clause expresses a complete thought.
The baby is sleeping.
By contrast, a subordinate clause does not:
Because the baby is sleeping
Put them together, however, and you get:
Because the baby is sleeping, we should be quiet.
To clarify further, the difference becomes clearer in a table:
| Feature | Independent Clause | Subordinate Clause |
| Has a subject and verb | Yes | Yes |
| Expresses a complete thought | Yes | No |
| Can stand alone | Yes | No |
| Also called | Main clause | Dependent clause |
| Example | She called me. | Because she needed help |
Consequently, a complex sentence normally contains an independent clause plus at least one subordinate clause.
How the Two Clauses Work Together
Fundamentally, subordination creates a relationship between ideas.
For example:
I stayed home because I was sick.
Here, the two ideas are not equally important: the main message is I stayed home, while the subordinate clause explains why.
Through this structure, you can communicate relationships such as:
- Cause: because I was sick
- Time: when the meeting ended
- Condition: if you need help
- Contrast: although it was expensive
- Purpose: so that everyone could hear
- Place: where the road ends
In this way, instead of presenting disconnected statements, you show readers exactly how the ideas relate.
Types of Subordinate Clauses
There are three major types of subordinate clauses:
- Adjective clauses
- Adverb clauses
- Noun clauses
Importantly, the key to identifying the type is function.
Rather than simply looking at the first word, ask what the entire clause does in the sentence.
| Type | Function | Example |
| Adjective clause | Modifies a noun or pronoun | The woman who called me is my teacher. |
| Adverb clause | Modifies or gives circumstances for an action | We left when the rain stopped. |
| Noun clause | Functions as a noun | I know what she wants. |
Adjective Clauses
An adjective clause, also called a relative clause, modifies a noun or pronoun.
Specifically, it provides information about which person, which thing, or what kind.
The book that you recommended was excellent.
Here, the clause that you recommended describes the noun book.
For comparison, you can set it alongside a regular adjective:
the interesting book
versus:
the book that you recommended
Both describe the noun book, though the second uses an entire clause to do so.
Common relative words include:
- who
- whom
- whose
- which
- that
- where
- when
For example:
The woman who lives next door is a doctor.
I found the keys that I lost yesterday.
This is the restaurant where we had dinner.
She remembers the year when they moved.
As a general rule, an adjective clause follows the noun or pronoun it modifies.
Restrictive and Nonrestrictive Adjective Clauses
Beyond this basic pattern, adjective clauses can provide either essential or additional information.
On one hand, a restrictive clause identifies exactly which noun you mean:
The employees who arrived early received breakfast.
Here, the clause identifies the employees in question, so removing it would change the intended meaning.
On the other hand, a nonrestrictive clause adds information that isn’t necessary to identify the noun:
My brother, who lives in Chicago, is visiting us.
In this case, the commas show that who lives in Chicago is additional information.
This distinction matters, then, because punctuation can change meaning.
Adverb Clauses
Turning next to adverb clauses, an adverb clause modifies a verb, adjective, or another adverb. Typically, it explains circumstances such as when, why, where, how, under what condition, or for what purpose.
For example:
We stayed inside because it was raining.
When the store opened, customers entered.
I’ll call you if I have time.
She spoke slowly so that everyone could understand.
Overall, common relationships include:
| Relationship | Common Words | Example |
| Time | when, while, before, after, until | After the movie ended, we left. |
| Reason | because, since, as | We stayed home because it rained. |
| Condition | if, unless | If you hurry, you’ll catch the bus. |
| Contrast | although, though, even though | Although he was tired, he continued. |
| Purpose | so that, in order that | She whispered so that nobody would hear. |
| Place | where, wherever | Sit wherever you feel comfortable. |
| Manner | as if, as though | He acted as if nothing happened. |
Additionally, adverb clauses are often flexible in position.
Because it was late, we went home.
We went home because it was late.
Either way, the meaning remains essentially the same, though the placement changes the sentence’s emphasis and punctuation.
Noun Clauses
Finally, a noun clause is a subordinate clause that performs a noun’s grammatical job.
Specifically, it can function as a:
- Subject
- Direct object
- Subject complement
- Object of a preposition
Consider, for instance:
What she said surprised everyone.
Here, the entire clause what she said acts as the subject.
Similarly:
I don’t know where he went.
In this case, the clause where he went functions as the object of know.
To confirm this, you can often test a noun clause by replacing it with it or another noun:
What she said surprised everyone.
It surprised everyone.
That substitution helps reveal the clause’s noun-like function.
Common words that introduce noun clauses include:
- that
- what
- who
- whether
- if
- why
- how
- when
- where
One important point worth noting, however, is that a noun clause can resemble a question but use normal statement word order.
For comparison:
Where is she?
versus:
I don’t know where she is.
Note that the second example contains a noun clause, not a direct question.
Words That Begin Subordinate Clauses
Generally, subordinate clauses are introduced by subordinating conjunctions or relative words.
Subordinating Conjunctions
Common subordinating conjunctions include:
- after
- although
- as
- because
- before
- even though
- if
- since
- so that
- than
- though
- unless
- until
- when
- whenever
- where
- wherever
- while
Typically, these words introduce adverb clauses.
For example:
Although the task was difficult, she completed it.
Relative Pronouns and Relative Adverbs
Meanwhile, relative clauses commonly begin with:
- who
- whom
- whose
- which
- that
- where
- when
- why
For example:
The student who won the award thanked her teacher.
Here, the clause describes student.
That said, the introductory word alone doesn’t always tell you the clause’s type. Consider when:
When the meeting ends, we’ll leave.
In this case, when the meeting ends is an adverb clause.
However:
I remember the day when we first met.
Here, by contrast, when we first met modifies day, making it a relative clause.
Ultimately, then, function matters more than the introductory word.
How to Identify a Subordinate Clause
Fortunately, you don’t need to memorize every grammar rule to find one. Instead, use a simple four-step test.
Find the Subject and Verb
First, look for a group containing its own subject and verb.
Because Maria was tired
Subject = Maria Verb = was
This tells you, in turn, that you’re dealing with a clause rather than a simple phrase.
Look for a Subordinating or Relative Word
Next, check whether the clause begins with a word such as:
- because
- although
- if
- when
- while
- who
- which
- that
- what
Often, these words signal dependence.
Test Whether It Can Stand Alone
After that, read the clause by itself.
Although Maria was tired.
Notice how it sounds incomplete.
Now, remove the subordinating word:
Maria was tired.
Notably, that can stand alone.
This “remove the trigger word” test is useful precisely because a subordinating word can turn an otherwise independent idea into a dependent clause.
Identify Its Function
Finally, ask what the clause does.
- Does it describe a noun? → Adjective clause
- Does it explain time, reason, condition, or another circumstance? → Adverb clause
- Does it act as a subject, object, or complement? → Noun clause
This final step, in particular, prevents many classification mistakes.
Subordinate Clause Examples
To see these principles in practice, here are examples in different sentence positions.
At the Beginning
Because the roads were flooded, the school closed.
Although she was nervous, she gave the presentation.
If you need anything, call me.
Notably, an introductory adverb clause is commonly followed by a comma.
At the End
The school closed because the roads were flooded.
She gave the presentation although she was nervous.
Call me if you need anything.
By contrast, an end-position adverb clause generally doesn’t need a comma when it follows the main clause closely.
In the Middle
Meanwhile, relative clauses frequently appear in the middle of sentences:
My sister, who lives nearby, visits every weekend.
The laptop that I bought last year still works perfectly.
Here again, the punctuation depends on whether the information is essential or additional.
Multiple Subordinate Clauses
Beyond a single clause, a sentence can also contain more than one subordinate clause:
When the meeting ended, I called the manager because I needed clarification.
In this example, when the meeting ended expresses time, while because I needed clarification expresses reason.
Above all, the important thing is to keep the relationships clear, since more clauses don’t automatically make writing better.
Punctuation Rules for Subordinate Clauses
As you might expect, subordinate clauses don’t all receive the same punctuation.
Instead, the comma depends on the clause’s position, function, and meaning.
Introductory Adverb Clauses
When an adverb clause comes before the main clause, a comma commonly separates the two:
After the guests arrived, we served dinner.
Because she was late, she took a taxi.
In this way, the punctuation helps readers recognize where the introductory dependent clause ends.
End-Position Adverb Clauses
Conversely, when the subordinate adverb clause follows the independent clause, a comma is often unnecessary:
We served dinner after the guests arrived.
She took a taxi because she was late.
That said, punctuation can vary when the clause is parenthetical or when a comma helps prevent ambiguity. Either way, the goal is always clear grammatical structure.
Restrictive Adjective Clauses
Similarly, a restrictive adjective clause is essential to the meaning and normally takes no commas:
The students who studied hard passed the exam.
Here, the clause identifies which students passed.
Nonrestrictive Adjective Clauses
By contrast, a nonrestrictive adjective clause adds information and is set off with commas:
My teacher, who has written three books, is giving a lecture.
In this case, the identity of my teacher is already clear, so the relative clause simply provides extra information.
Case study: To illustrate further, imagine a company has several managers.
The manager who approved the budget will attend the meeting.
Here, the clause identifies the specific manager.
Now, by contrast, imagine everyone already knows which manager you mean:
Sarah, who approved the budget, will attend the meeting.
In this version, the second clause adds information rather than identifying Sarah, which is exactly why commas matter.
Common Errors With Subordinate Clauses
Using a Subordinate Clause as a Complete Sentence
First, this creates a sentence fragment:
Because I was tired.
Naturally, the reader expects more information.
Correct:
Because I was tired, I went to bed early.
Creating a Comma Splice
Next, a comma splice occurs when two independent clauses are incorrectly joined with only a comma.
Incorrect:
I was tired, I went to bed.
Correct:
I was tired, so I went to bed.
Or, alternatively:
I was tired. I went to bed.
Or:
I went to bed because I was tired.
Notably, this third version uses subordination to make one idea dependent on the other.
Misplacing a Subordinate Clause
In addition, a modifier should appear close to the word it describes.
Unclear:
She served sandwiches to the children that were on paper plates.
As written, this can momentarily suggest that the children were on paper plates.
Clearer:
She served the children sandwiches that were on paper plates.
In short, good clause placement prevents awkward or unintended meanings.
Confusing a Phrase With a Clause
Finally, a phrase does not contain the same subject-verb combination required of a clause.
Compare:
Because of the rain — phrase
Because it rained — subordinate clause
While the first contains no subject-verb pair, the second contains it and rained.
This distinction, therefore, is important when analyzing sentence structure.
Subordinate Clause vs. Other Clause Types
Taken together, understanding the differences makes grammar much easier.
| Structure | Main Feature | Example |
| Independent clause | Can stand alone | She finished the work. |
| Subordinate clause | Depends on another clause | because she had time |
| Phrase | Does not contain a complete subject-verb relationship | after lunch |
| Complex sentence | Independent clause + subordinate clause | She finished because she had time. |
| Compound-complex sentence | Multiple independent clauses + subordinate clause(s) | She finished because she had time, and she submitted it early. |
Notably, a common mistake is assuming that every group of words containing a verb is an independent clause. Rather, independence depends on the clause’s grammatical relationship, not simply on having a subject and verb.
Why Subordinate Clauses Matter in Writing
Ultimately, subordinate clauses give you control over which idea receives emphasis.
Compare, for instance:
The weather was bad. We canceled the picnic.
While these sentences are correct, the relationship between them is only implied.
Now, write instead:
Because the weather was bad, we canceled the picnic.
Here, the relationship is made explicit.
In this way, subordination can show:
- Cause and effect
- Time
- Condition
- Contrast
- Purpose
- Place
- Manner
- Additional description
At the same time, it also helps writers avoid a long string of short, disconnected sentences.
Combine Related Ideas
For example, instead of:
The store was crowded. I left.
You can write:
Because the store was crowded, I left.
In doing so, the new sentence tells readers why the action happened.
Emphasize the More Important Idea
Similarly, compare:
Although the product was expensive, customers bought it.
Here, the main point is that customers bought it, while the price is presented as a contrasting circumstance.
Alternatively, you can reverse the structure:
Customers bought the product although it was expensive.
Even so, the relationship remains, though the sentence now begins with the main idea.
Vary Sentence Structure
Beyond emphasis, strong writing doesn’t rely on one sentence pattern.
For that reason, you can place subordinate clauses before or after the independent clause:
When the alarm rang, everyone left.
Everyone left when the alarm rang.
Overall, this flexibility creates more natural sentence rhythm.
Avoid Overloading Sentences
Nevertheless, subordination is useful, but more isn’t always better.
Compare:
Because the meeting ended when the manager arrived, although everyone was still waiting, we left because we had another appointment.
Here, the sentence contains too many competing relationships.
Instead, shorter sentences may communicate the same information more clearly.
In short, good writing uses subordinate clauses to clarify relationships, not to make sentences look complicated.
Subordinate Clause Quick Reference
For convenience, keep this table handy when reviewing your writing:
| Question | Answer |
| What is a subordinate clause? | A dependent clause that cannot normally stand alone. |
| What else is it called? | A dependent clause. |
| Does it contain a subject and verb? | Yes. |
| Can it stand alone? | No. |
| Main types? | Adjective, adverb, and noun clauses. |
| Adjective clause function? | Modifies a noun or pronoun. |
| Adverb clause function? | Gives information such as time, reason, or condition. |
| Noun clause function? | Acts as a noun in the sentence. |
| Common signals? | Subordinating conjunctions and relative words. |
| Can it begin a sentence? | Yes. |
| Does it always need a comma? | No. |
Frequently Asked Questions About Subordinate Clauses
Q1. What Is a Subordinate Clause?
A subordinate clause is a group of words with a subject and verb that cannot normally stand alone as a complete sentence. It depends on an independent clause to express a complete thought.
Q2. What Is Another Name for a Subordinate Clause?
Dependent clause is the most common name for a subordinate clause. Both terms describe a clause that depends on another clause to form a complete sentence.
Q3. Can a Subordinate Clause Stand Alone?
No. A subordinate clause usually becomes a sentence fragment when it stands alone. For example, “Although she was tired” needs an independent clause such as “she continued working.”
Q4. What Are the Three Main Types of Subordinate Clauses?
The three commonly taught types are adjective clauses, adverb clauses, and noun clauses. Each type has a different grammatical function within a sentence.
Q5. How Can I Identify a Subordinate Clause?
Look for a group of words containing a subject and verb. Then check whether it begins with a subordinating or relative word and whether it can express a complete thought by itself.
Q6. What’s the Difference Between a Subordinate Clause and an Independent Clause?
An independent clause can stand alone and express a complete thought. A subordinate clause cannot normally stand alone and needs an independent clause to complete its meaning.
Q7. Do Subordinate Clauses Always Need Commas?
No. An introductory adverb clause often takes a comma, as in “When the rain stopped, we left.” An end-position adverb clause usually doesn’t need one.
Q8. Can a Sentence Have More Than One Subordinate Clause?
Yes. A sentence can contain two or more subordinate clauses. For example, “When I arrived, she told me what had happened” contains an adverb clause and a noun clause.
Q9. Can a Subordinate Clause Come at the Beginning of a Sentence?
Yes. Adverb clauses often appear at the beginning, as in “If you need help, call me.” Their position depends on their grammatical function and the writer’s intended emphasis.
Q10. What’s the Difference Between a Subordinate Clause and a Phrase?
A subordinate clause contains a subject-verb relationship, while a phrase doesn’t. For example, “Because she was sick” is a subordinate clause, but “Because of her illness” is a phrase.
Conclusion
A subordinate clause contains a subject and verb, but it cannot normally stand alone as a complete sentence. The three major types are adjective clauses, adverb clauses, and noun clauses, each serving a different function. To identify one, find the subject and verb, check whether it can stand alone, and determine its grammatical role. Once you understand these patterns, you can build clearer sentences, connect ideas naturally, and avoid common grammar and punctuation mistakes.