Sentence Structures

Main Learning Goal and Core Concepts: The goal of this lesson is to learn about the fourth sentence structure in English: Compound-Complex sentences. This sentence structure helps essay writing flow smoother and challenges students to combine basic knowledge from previous sentence structures such as simple, compound, and complex sentences.


Compound Sentence Structure

A compound sentence is made up of two independent clauses joined by a coordinating conjunction (for, and, nor, but, or, yet, or so) and a comma or by a semicolon alone.

Complex Sentence Structure

A complex sentence contains an independent clause and at least one dependent clause (sometimes called a subordinate clause).


Lesson Brief

Lesson Brief: In this lesson, we will learn about compound-complex sentences. These sentences combine characteristics from both compound (two independent clauses) and complex sentences (independent + dependent clauses). These sentences will be joined by a conjunction in order to complete a sentence. 

The compound-complex sentence combines compound and complex sentences together. Understanding how to construct the compound-complex sentence will give you another tool to add to the complexity of your writing.

A compound-complex sentence consists of at least two independent clauses and one or more dependent clauses.

Example: Though Mitchell prefers watching romantic films, he rented the latest spy thriller, and he enjoyed it very much. 


The conjunctions used to combine the two sentences together are FANBOYS (or, And, Nor, But, Or, Yet, and So) and subordinating conjunctions

  • FANBOYS is a mnemonic device, which stands for the coordinating conjunctions: For, And, Nor, But, Or, Yet, and So. They are used to join two or more independent clauses together and must have a comma right before it.
  • Subordinating conjunctions are used to introduce a dependent clause.
    • Commonly used: if, while, though


While independent clauses can be found easily, it is much more difficult to spot dependent clauses. In these examples, the dependent, or subordinate, clause is underlined.

  1. When I grow up, I want to be a ballerina, and my mom is proud of me.
  2. I will get to watch television, but first, I have to clean up the dishes after we finish eating.
  3. We won the game, but my uniform was muddy because it rained the entire time.
  4. After our trip to the beach, school started back, and I was excited to see my friends.
  5. Sarah cried when her cat got sick, but he soon got better.
  6. The sun is shining through the clouds, so I think that we can go swimming.

Words to use when starting a sentence:

  • Since,
  • However,
  • Due to fact that,


  • Compound-complex sentences are used to express a long chain of thought.
  • Make sure to break down the sentences in order to check if they are run-on or not. Take a look at our worksheet on run-on sentences here.
  • Construct the sentence by first making a compound sentence, then a complex sentence and find the appropriate FANBOYS and subordinating conjunction to make the sentences stick together.

If you want another online writing lesson, additional information can be found here and here.

If you would like a blank copy of our Compound-Complex Sentence Structure worksheet along with corresponding answers, they can be found below:

Compound-Complex Sentence Structures Blank Worksheet

Compound-Complex Sentence Structures Worksheet with Answers