Understanding what is a subordinate clause can make English grammar much easier to follow. A subordinate clause is a group of words that contains a subject and a verb but does not express a complete thought on its own. Because it depends on another clause to make sense, it is also called a dependent clause. You’ll often see subordinate clauses beginning with words such as because, although, when, if, since, and while. These words help connect ideas and show relationships between different parts of a sentence.
Subordinate clauses add useful information to sentences by explaining when, why, where, how, or under what condition something happens. For example, in the sentence, “I stayed home because it was raining,” the clause because it was raining explains why the person stayed home. It cannot stand alone as a complete sentence, but it gives the main clause more meaning. This makes subordinate clauses an important part of both everyday communication and formal writing.
Learning how subordinate clauses work can also help you identify sentence structures and avoid common grammar mistakes. They can appear at the beginning, middle, or end of a sentence, depending on the information you want to emphasize. In this guide, you’ll learn the definition, types, examples, punctuation rules, and practical ways to recognize and use subordinate clauses correctly.
What Is a Subordinate Clause?
A subordinate clause is a group of words that contains a subject and a verb but cannot stand alone as a complete sentence.
Because it does not express a complete thought, it depends on an independent clause to make sense.
Consider this example:
Because it was raining
The clause contains:
- Subject: it
- Verb: was raining
However, the thought feels incomplete. Readers naturally ask:
What happened because it was raining?
Now look at the complete sentence:
Because it was raining, we canceled the picnic.
The subordinate clause provides additional information, while the independent clause completes the meaning.
Simple Definition
A subordinate clause is:
- A dependent clause
- Contains a subject and verb
- Cannot stand alone as a sentence
- Depends on an independent clause
Quick Formula
| Component | Requirement |
| Subject | Yes |
| Verb | Yes |
| Complete Thought | No |
| Can Stand Alone | No |
| Depends on Another Clause | Yes |
Why Subordinate Clauses Matter in Writing
Many writers rely heavily on short, simple sentences.
For example:
The meeting ended. Everyone went home. It was late.
The sentences are correct, but they sound repetitive.
Now look at the revised version:
Because it was late, everyone went home after the meeting ended.
The second sentence flows better because the subordinate clause connects ideas logically.
Benefits of Using Subordinate Clauses
Subordinate clauses help writers:
- Add detail and context
- Improve sentence variety
- Create smoother transitions
- Show cause and effect
- Express conditions
- Compare ideas
- Explain time relationships
- Improve readability
Professional writers frequently use subordinate clauses because they allow complex ideas to fit into concise sentences.
How to Identify a Subordinate Clause
Many learners know the definition but struggle to spot subordinate clauses in actual sentences.
Fortunately, identification becomes easy when you follow a simple process.
Look for a Subject and Verb
A subordinate clause always contains both.
Example:
Although she studied hard
Subject: she
Verb: studied
Check for an Incomplete Thought
Ask yourself:
Can this stand alone as a complete sentence?
If not, it may be a subordinate clause.
Look for Signal Words
Many subordinate clauses begin with words such as:
- Because
- Although
- Since
- While
- Unless
- If
- When
- After
- Before
- Until
Example:
Although the road was icy
This thought feels unfinished.
Test It
Add an independent clause:
Although the road was icy, the driver arrived safely.
Now the sentence is complete.
The Three Main Types of Subordinate Clauses
Grammar experts generally divide subordinate clauses into three primary categories:
- Adverbial clauses
- Adjective clauses
- Noun clauses
Each serves a different purpose.
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Adverbial Subordinate Clauses
An adverbial clause functions like an adverb.
It modifies a verb, adjective, or another adverb.
These clauses answer questions such as:
- When?
- Why?
- How?
- Under what condition?
- To what extent?
Examples
Because she practiced daily, she improved quickly.
After the movie ended, everyone left.
If you work hard, you will succeed.
Common Adverbial Clause Connectors
| Purpose | Common Words |
| Time | when, after, before, while |
| Cause | because, since, as |
| Condition | if, unless, provided that |
| Contrast | although, though, whereas |
| Purpose | so that, in order that |
Real-World Example
Business writing often uses adverbial clauses:
Because customer demand increased, the company expanded production.
The clause explains why the action occurred.
Adjective Subordinate Clauses
An adjective clause describes a noun or pronoun.
You may also hear it called a relative clause.
These clauses usually begin with:
- Who
- Whom
- Whose
- Which
- That
Examples
The student who won the award received a scholarship.
The book that I purchased yesterday is excellent.
The car which was parked outside disappeared overnight.
In each sentence, the subordinate clause provides more information about a noun.
Quick Breakdown
| Noun | Adjective Clause |
| Student | who won the award |
| Book | that I purchased yesterday |
| Car | which was parked outside |
Why Writers Use Adjective Clauses
Without adjective clauses:
I met a woman. She owns a bakery.
With an adjective clause:
I met a woman who owns a bakery.
The sentence becomes more concise and natural.
Noun Subordinate Clauses
A noun clause acts as a noun within a sentence.
It can function as:
- Subject
- Object
- Subject complement
Examples
What he said surprised everyone.
I know that she is correct.
The problem is that nobody listened.
Noun Clauses as Subjects
Example:
What you decide matters.
The entire clause serves as the subject.
Noun Clauses as Objects
Example:
We believe that the project will succeed.
The clause functions as the object of the verb.
Common Noun Clause Starters
- That
- What
- Who
- Whoever
- Whether
- Why
- How
Practical Example
Academic writing frequently uses noun clauses:
Researchers discovered that sleep improves memory retention.
The clause acts as the object of the verb discovered.
Subordinate Clause vs Independent Clause
Many students confuse subordinate and independent clauses.
The distinction is simple.
Independent Clause
An independent clause:
- Contains a subject
- Contains a verb
- Expresses a complete thought
- Can stand alone
Example:
The team won the championship.
Subordinate Clause
A subordinate clause:
- Contains a subject
- Contains a verb
- Does not express a complete thought
- Cannot stand alone
Example:
Although the team was inexperienced
Comparison Table
| Feature | Independent Clause | Subordinate Clause |
| Subject | Yes | Yes |
| Verb | Yes | Yes |
| Complete Thought | Yes | No |
| Can Stand Alone | Yes | No |
| Requires Another Clause | No | Yes |
Side-by-Side Example
Subordinate clause:
Because the store was closed
Independent clause:
We returned home.
Complete sentence:
Because the store was closed, we returned home.
FAQs
What is a subordinate clause in simple terms?
A subordinate clause is a group of words with a subject and verb that does not form a complete sentence by itself. It needs a main clause to express a complete thought.
How can you identify a subordinate clause?
Look for a group of words containing a subject and verb that begins with a subordinating word such as because, although, when, if, since, or while. Then check whether it can stand alone as a complete sentence.
Can a subordinate clause stand alone?
No. A subordinate clause is dependent on a main clause. If you use it alone, it usually becomes a sentence fragment.
Does a subordinate clause always come first?
No. A subordinate clause can appear at the beginning, middle, or end of a sentence. Its position depends on how the writer wants to organize the information.
What is an example of a subordinate clause?
In the sentence “We canceled the picnic because it was raining,” the words because it was raining form a subordinate clause. They explain the reason for canceling the picnic but cannot stand alone as a complete sentence.
Conclusion
A subordinate clause is a dependent group of words containing a subject and a verb that cannot express a complete thought by itself. It relies on a main clause to create a complete sentence. Subordinate clauses often begin with subordinating conjunctions such as because, although, if, when, and while. They can provide information about time, reason, condition, contrast, place, and other relationships between ideas.
Once you understand how these clauses function, you can build clearer and more detailed sentences. Recognizing the difference between a main clause and a subordinate clause also helps you avoid sentence fragments and punctuation errors. With regular practice and plenty of examples, using subordinate clauses becomes much more natural and can significantly improve your everyday writing and communication.
