Complex Sentences
Learn how to combine independent and dependent clauses to create complex sentences
What Are Complex Sentences?
A complex sentence is a sentence that contains one independent clause and at least one dependent clause. Complex sentences help you express more detailed and nuanced ideas by showing relationships between different thoughts.
Structure of Complex Sentences
Independent Clause
A complete thought that can stand alone as a sentence.
Example: I went to the park.
Dependent Clause
An incomplete thought that cannot stand alone and depends on the independent clause.
Example: because it was sunny
Combined Example
I went to the park because it was sunny.
Common Subordinating Conjunctions
Complex Sentences in Context
Although it was raining, we went outside to play.
She finished her homework before she watched TV.
If you study hard, you will do well on the test.
When the bell rings, the students go to class.
Interactive Quiz 1: Identify Clauses
Identify the independent and dependent clauses:
Because it was late, we went home.
Show Answer
Dependent: Because it was late | Independent: we went home
She smiled when she saw her friend.
Show Answer
Independent: She smiled | Dependent: when she saw her friend
If you are ready, we can begin.
Show Answer
Dependent: If you are ready | Independent: we can begin
Interactive Quiz 2: Combine Clauses
Combine the clauses to make a complex sentence:
I finished my work. I could go outside. (since)
Show Answer
Answer: Since I finished my work, I could go outside.
He was tired. He kept working. (although)
Show Answer
Answer: Although he was tired, he kept working.
You call me. I will help you. (if)
Show Answer
Answer: If you call me, I will help you.
Interactive Quiz 3: Punctuation in Complex Sentences
Choose the correct punctuation:
_____ If you finish early, we can go to the park.
Show Answer
Answer: Comma after the dependent clause: If you finish early, we can go to the park.
We will eat dinner _____ after we get home.
Show Answer
Answer: No comma needed: We will eat dinner after we get home.
Interactive Quiz 4: Create Complex Sentences
Create complex sentences using these conjunctions:
because
Show Example
Example: I stayed inside because it was raining.
although
Show Example
Example: Although I was tired, I finished my homework.
since
Show Example
Example: Since you asked, I will help you.
Important Grammar Rules for Complex Sentences
Comma Usage
Use a comma after a dependent clause that comes before the independent clause.
No Comma Needed
No comma is needed if the dependent clause comes after the independent clause.
Subordinating Conjunctions
Use subordinating conjunctions to connect clauses in complex sentences.
Quick Reference
Pro Tip
Complex sentences make your writing richer and more interesting!