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Sentence Structure

There are three basic types of sentence structure: simple sentences, compound sentences, and complex sentences. Review the sections below for examples of each type.

Independent clause (subject + verb + what is needed for complete idea)

Jane reads the textbook. 

  • Jane is the subject
  • reads is the verb
  • the textbook completes the idea

Compound sentences use coordinating conjunctions:
FANBOYS [F = for;  A = and;  N = nor;  B = but;  O = or;  Y = yet;  S = so]

Independent clause, + coordinating conjunction + independent clause.
*Notice the comma after the first clause.

He could not attend the presentation, for he was studying that night.

The first patient has osteoporosis, and the second has diabetes.

I like learning new information, but I'm tired of studying now.

I'm hungry, so I'm going to make some dinner.

Complex sentences use subordinating conjunctions. WISEABOUT is an acronym to help you remember coordinating conjunctions.

W       when, whenever, wherever, whereas, whether, while
I         if
S        since, so that
E        even though
A        after, although, as
B       because, before
O       once
U       unless, until
T        though

Adding a subordinating conjunction to an independent clause changes the independent clause into a dependent clause.

There are two formulas for a complex sentence:

Formula #1
Independent clause +  dependent clause.

I am tired because I stayed up late last night.
*Notice that there is no comma when the dependent clause is at the end of the sentence.
Formula #2     
Dependent clause, independent clause.

Because I stayed up late last night, I am tired.
*When the dependent clause is at the beginning of the sentence, add a comma before the independent clause.