What Is A Main Clause? Definition & Examples
Confused by clauses? You’re not alone. Grammar can sometimes feel overwhelming, but understanding the building blocks of sentences – especially main clauses – is crucial for clearer and more powerful writing.
In this blog, I’ll explain what a main clause is, how it differs from subordinate clauses and how they appear in sentences with a little quiz at the end to test yourself!
Ready to finally understand main clauses? Let’s get started!
What is a Main Clause?
In English grammar, a main clause is a group of words that contains a subject and a verb and expresses a complete thought. It can stand alone as a sentence because it doesn’t rely on other clauses to make sense which is why it is also referred to as an independent clause. Think of it as the foundation of your sentences.
They can be used on their own or combined with other clauses to add depth and complexity; for example, 2 or more main clauses would create a compound sentence, but we’ll get into this later.
Just remember this: every complete sentence must have at least one main clause!
Key Characteristics of a Main Clause:
• It contains a subject and a verb.
• It expresses a complete thought.
• It can stand alone as a complete sentence.
Examples:
1. She walked to the store.
In this example, “she” is the subject, “walked” is the verb, and the sentence expresses a complete thought, making it a main clause. It’s an example of a simple sentence. Here are some more examples:
2. The cat slept on the couch.
• Subject: The cat, Verb: slept. It expresses a complete thought.
3. He finished his homework.
• Subject: He, Verb: finished. A complete sentence on its own.
4. They danced all night.
• Subject: They, Verb: danced. It can stand alone as a sentence.
5. The sun rises in the east.
• Subject: The sun, Verb: rises. It conveys a complete idea.
How A Main Clause Differs From A Subordinate Clause
A subordinate clause (also known as a dependent clause) differs from a main clause in that it cannot stand alone as a complete sentence. It provides additional information but needs to be attached to a main clause to make sense.
Subordinate clauses often begin with subordinating conjunctions like because, although, if, or when. Their function is to add details, clarify circumstances, or explain reasons within a sentence.
Example of Subordinate Clauses:
1. While walking to the store.
This clause contains a verb (‘walking’) but doesn’t express a complete thought and cannot stand alone as a sentence. It’s a subordinate clause that leaves the reader wondering what happened “while walking to the store.” Here are some more examples:
2.. Because she was tired.
• Although this has a subject (she) and a verb (was), it doesn’t express a complete thought and leaves the reader waiting for more information.
3. While the dog barked.
• Contains a subject (the dog) and a verb (barked), but it doesn’t form a complete idea and needs a main clause to explain what happened.
4. If he goes to the party.
• This is a conditional clause that cannot stand alone; it needs more information to form a complete thought.
5. Although it was raining.
• This clause leaves the reader expecting more context. It introduces a situation but doesn’t form a complete sentence.
Key Differences:
• A main clause can stand alone as a sentence; a subordinate clause cannot.
• A subordinate clause depends on the main clause to provide full meaning.
• The main clause carries the primary message, while the subordinate clause adds supplementary information.
Putting Clauses Together In Compound and Complex Sentences
So, what happens when we combine a main clause with a subordinate clause? You get a complex sentence!
Complex Sentences with a Main Clause
A complex sentence links the main clause with a subordinate clause using coordinating conjunctions like and, but, or, because or a semicolon.
Example:
She finished her essay because the deadline was approaching.
• Main Clause: She finished her essay (the main action, which could stand alone as a full sentence).
• Subordinate Clause: because the deadline was approaching (adds context but can’t stand alone).
In this complex sentence, the main clause conveys the primary action (finishing the essay), while the subordinate clause explains why the action occurred (the approaching deadline). The main clause forms the foundation of the sentence, with the subordinate clause providing additional detail.
Compound Sentences with a Main Clause
What about combining a main clause with another main clause? You get a compound sentence!
Example:
She finished her essay, and she submitted it to her professor.
• Main Clause 1: She finished her essay (this could stand alone).
• Main Clause 2: She submitted it to her professor (this could also stand alone).
Here, the two main clauses are linked by and to show that the actions happened one after the other. Both main clauses hold equal importance in conveying the full meaning.
Mistakes That Can Happen With Main Clauses
Even when you understand the basics of main clauses, it’s easy to make mistakes in sentence construction. Here are some of the most common errors to watch out for:
1. Run-On Sentences
Run-on sentences happen when two or more main clauses are joined together improperly, without the correct punctuation or conjunction. These sentences can confuse the reader and make it hard to follow the flow of your ideas. For example, “I went to the store I bought some milk” is a run-on sentence. To fix this, you can add a period or a coordinating conjunction like and: “I went to the store, and I bought some milk.”
2. Fragmented Sentences
A fragment occurs when a group of words lacks a necessary element, such as a subject or a verb, making it incomplete. Sentence fragments often result from treating a subordinate clause as though it can stand alone, or simply leaving out a key element. For example, “Running down the street” is a fragment because it lacks a subject. To fix this, you need to include the subject and complete the thought: “He was running down the street.”
3. Using The Wrong Punctuation
When two main clauses are combined in a sentence, there are a few ways to punctuate them correctly:
• Comma + Coordinating Conjunction: Use a comma followed by a coordinating conjunction like and, but, or, so, yet. For example: She studied hard, and she passed the exam.
• Semicolon: You can use a semicolon to link two related main clauses without using a conjunction. For example: She studied hard; she passed the exam.
• Full Stop: If the clauses are unrelated, you can use a full stop to separate them into two distinct sentences.
Incorrectly linking two main clauses without proper punctuation can result in a run-on sentence, which confuses readers.
• Subordinate Clauses: If the sentence begins with a main clause and then a subordinate clause, you don’t need punctuation between them. She bought groceries because the fridge was empty. This is simple, great!
But if the subordinate clause comes before the main clause you’ll need a comma to separate them: Because the fridge was empty, she bought groceries.
Quiz: Can You Identify the Main Clause?
Now that you’ve learned what about main clauses, let’s test your knowledge! Look at the following sentences and identify the main clause(s):
1. While he was studying, he drank three cups of coffee.
A. While he was studying
B. He drank three cups of coffee
(Answer: B, He drank three cups of coffee)
2. I baked a cake, and it turned out perfectly.
A. I baked a cake
B. And it turned out perfectly
(Answer: A, I baked a cake)
3. Because the weather was terrible, the game was cancelled.
A. Because the weather was terrible
B. The game was cancelled
(Answer: B, The game was cancelled)
4. She forgot her keys, so she went back to the house.
A. She forgot her keys
B. So she went back to the house
(Answer: A, She forgot her keys)
5. The sun was setting, and the birds began to sing.
A. The sun was setting
B. The birds began to sing
(Answer: Both A and B are main clauses as it is a compound sentence.)
6. When the bell rang, the students rushed out of the classroom.
A. When the bell rang
B. The students rushed out of the classroom
(Answer: B, The students rushed out of the classroom is the main clause, while When the bell rang is a subordinate clause.)
7. She could either study for the test, or she could go to the party.
A. She could either study for the test
B. She could go to the party
(Answer: Both A and B are main clauses as it is a compound sentence.)
8. After he finished his homework, he played video games for an hour.
A. After he finished his homework
B. He played video games for an hour
(Answer: B, He played video games for an hour is the main clause, while After he finished his homework is a subordinate clause.)
Great Job, You Know All About Main Clauses
Whether it’s a simple sentence or part of a sentence in a more complex structure, mastering the use of main clauses and their punctuation will enhance the flow and clarity of your work. Just remember, a main clause contains a subject and verb and can stand on its own as a complete thought!
