What are simple, compound and complex sentences?
A simple sentence, also known as a main clause, shows one clear idea. It has one subject (what or who) and one verb (a doing word).
Scottstruggles through the snow.
A compound sentence joins two equal main clauses using a coordinating conjunction.
Oates helps Scott, but the cold bites at them both.
A complex sentence adds a subordinate clause to a main clause.
The team struggles on through the snow even though Oates was injured.
What is a simple, compound and complex sentence?
Learn more about simple, compound, and complex sentences with this script about Captain Scott's expedition to the South Pole. Then, put your knowledge to the test in the quiz!
The differences between simple, compound and complex sentences
There are different types of sentences you can use in your writing and each one helps you share ideas in a slightly different way.
Simple sentence
A simple sentence expresses one complete idea with a single subject and verb.
Roald Amundsen travelled from Norway.
Compound sentence
A compound sentence joins two simple sentences, or main clauses, using a coordinating conjunction (for, and, nor, but, or, yet, so).
Amundsen's team travelled quickly, and they reached the South Pole first.
Complex sentence
A complex sentence combines a main clause with a subordinate clause.
Scott's team realised they had been beaten to the pole when they saw the flag in the distance.
Subordinate clauses can appear at the start, middle or end of a sentence, but they can never stand alone as a complete sentence.
When they saw the flag in the distance, Scott's team realised they had been beaten to the pole.
Scott's team, when they saw the flag in the distance, realised they had been beaten to the pole.
Example 1
Which sentence below is a compound sentence?
a) Captain Oates stepped outside because he didn’t want to slow his team down.
b) The men marched through the snow.
c) The explorers fought the blizzard, and they never gave up.
✓ c) is a compound sentence.
c) joins two main clauses with the coordinating conjunction (and), so it's a compound sentence.
a) is a complex sentence. It has a main clause (Captain Oates stepped outside) and a subordinate clause (because he didn’t want to slow his team down).
b) is a simple sentence, because it has one subject and one verb and expresses a single idea.
Example 2
Which part of the complex sentence below is the subordinate clause?
Although you are weak, we can get through this together.
✓ 'Although you are weak' is the subordinating clause.
This clause does not make sense on its own, it depends on the main clause 'we can get through this together' to be understood.
Task
Sentence odyssey!
It’s your turn to write your own epic adventure with simple, compound and complex sentences.
How about a trek up a cloud-topped mountain, maybe a journey through dark tunnels to a secret underground cave or even a cosmic space exploration to the stars?
You could start with:
- A simple sentence about the weather.
- A compound sentence about teamwork.
- A complex sentence showing determination.
Writing is a lot like music. Different sentence types create different rhythms, so mixing them in different ways keeps your writing interesting and engaging.
Play our fun English game Crystal Explorers! game
Use grammar, punctuation and spelling skills to explore jungles, caves and tombs on your mission.
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