How to write a complex sentence

  • There are three types of sentence - simple, compound and complex.
  • Using complex sentences can make it easier to add layers of information and detail when writing.
  • Complex sentences have at least one subordinate clause that adds more detail and information to the sentence.
Learn the differences between simple, compound and complex sentences.

There are three types of sentence - simple, compound and complex. All three have an equally important role in writing.

Complex sentences can be useful for presenting ideas that need layers of information and details. In order to understand complex sentences, it’s helpful to first look at simple and compound sentences.

Simple sentences

Simple sentences have just one main verb, for example:

‘He walked quickly back to the house.’

Simple sentences are important for making clear points. They are also useful for creating tension when writing fiction. However, if you only ever use simple sentences in your writing, the reader might lose interest in what you are saying. Too many simple sentences can make writing seem disjointed. To hold a reader’s interest, it’s important to use a variety of sentence types.

A simple sentence contains only one main verb, or doing word, such as the verb ‘to walk’

Compound sentences

A compound sentence has more than one verb. The two, or more, clauses of the sentence still make sense on their own. Compound sentences often use coordinating conjunctions, such as ‘but’, ‘and’ and ‘so’:

‘George realised he could hear voices, so he walked quickly back to the house.’

Compound sentences are useful for connecting events and ideas in your writing. Only using compound sentences could make your writing sound less sophisticated.

Complex sentences

Subordinate clauses

Subordinate clauses are sometimes known as dependent clauses, because they need the main part of the sentence to make sense. They don’t make complete sense on their own:

‘George wanted to stay outside, despite the driving rain and wind.’

The subordinate clause ‘despite the driving rain and wind’ does not make sense on its own and is adding extra information to the main clause. Subordinate clauses can be an effective way to add more detail to your writing.

Subordinate conjunctions

A subordinate clause usually begins with a subordinate conjunction, such as:

  • although
  • because
  • even though
  • despite
  • when

This type of conjunction signals to the reader that this part of the sentence is adding additional information to the main part of the sentence.

The subordinate clause can go at the start, in the middle or at the end of the sentence:

  • Even though it was getting dark, Sam wanted to go for a walk.’
  • ‘Sam, even though it was getting dark, wanted to go for a walk.’
  • ‘Sam wanted to go for walk even though it was getting dark.’

A subordinate clause may also be introduced by a relative pronoun - a word like ‘that’, ‘which’, ‘who’ or ‘whose’:

‘Sam, who didn’t like the dark, stayed at home.’

A subordinate clause, such as ‘despite the driving ‘rain and wind’ adds detail to a sentence

Developing a complex sentence

Simple - ‘George was feeling excited. It was dark in the forest.’

Compound - ‘George was feeling excited and it was dark in the forest.’

Complex - ‘George was feeling excited, despite the darkness of the forest.’

The complex sentence example presents the reader with a more interesting idea and shows the relationship between George feeling excited and the darkness of the forest.

A complex sentence isn’t always better but when used correctly can add more sophistication to your writing. Just as with simple and compound sentences, too many complex sentences in a row might lose the reader's engagement. Think carefully about the effect you wish to create for the reader when you choose sentence types.


Test your knowledge of how to write a complex sentence in this short quiz!

Where next?

How to use linguistic devices in your writing
How to structure and punctuate direct speech in fiction
How to use structure for effect