The United States of America is a union of fifty states and is the third largest country in the world

Using Complex Sentences With Other Sentence Types

Complex sentences help you combine ideas in an interesting way. When you use them with other sentence types in your writing, the variety helps you avoid choppiness and dull repetition. Each sentence type has a set number of clauses:

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  Simple sentences have one independent clause
  
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  Compound sentences have at least two independent clauses
  
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  Complex sentences have one independent clause and at least one dependent clause
  
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  C ompound-complex sentences have at least two independent clauses and at least one dependent clause
  

Examples of Complex Sentences

Below are examples of complex sentences. In each example, the independent clause is shaded. The dependent clause is unshaded.

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  Stay in the bath until the phone rings.
  
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  The car swerved to miss Mrs Jackson, who had slipped off the pavement.
  
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  Both the cockroach and the bird would get along very well without us, although the cockroach would miss us most. (Joseph Wood Krutch, 1893-1970)
  
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  Leave while you can.
  
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  When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong. (Arthur C. Clarke)
  

(This is two complex sentences.)

The Four Types of Sentence Structure

A complex sentence is one of four main sentence structures, all of which are shown below. In these examples, the independent clauses are shaded.

A Complex Sentence. A complex sentence has an independent clause and at least one dependent clause. For example:

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  The human brain never stops working until you stand up to speak in public.
  

A Compound Sentence. A compound sentence has at least two independent clauses. For example:

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  I always wanted to be somebody, but I should have been more specific. (Jane Wagner)
  

A Simple Sentence. A simple sentence has just one independent clause. For example:

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  Curiosity killed the cat.