Grammar Sentence Structures 2016-04-15 00:00

What Are Simple, Compound, and Complex Sentences?

What are simple, compound, and complex sentences?

One thing that ProWritingAid is great at pointing out is the variety of sentence lengths you use in your writing. You know that varying the lengths creates a more lyrical bend to your writing. You don’t want all short sentences. Nor do you want all long sentences that complicate your reader’s understanding.

Simple, compound, and complex sentences are all ways of varying the length. Let’s see how they work.

  1. Simple Sentences
  2. Compound Sentences
  3. Complex Sentences

Simple Sentences

A simple sentence has only the most elemental building blocks of a sentence: a subject and a verb used in a complete thought, also called an independent clause.

Here are some examples of simple sentences:

  • Kristina drank her morning coffee. (Kristina = subject, drank = verb)

  • Kristina showered and dressed. (Kristina = subject, showered and dressed = compound verbs)

Simple sentences are usually short. You may use compound subjects and verbs to add length, but for the most part, using too many simple sentences makes your writing choppy.

Compound Sentences

Compound sentences marry two independent clauses together with a conjunction.

  • Kristina drank her morning coffee, and then she showered and dressed.

Notice the first part of the sentence and the last part can stand alone as independent sentences. The key is to not use too many compound sentences together or your writing will sound stilted.

Complex Sentences

A complex sentence uses an independent clause combined with one or more dependent clauses. A dependent clause is similar to an independent clause, but it can’t stand on its own as a complete sentence. Complex sentences use conjunctions to tie them together, too.


  • Because she woke up late when her alarm malfunctioned, Kristina missed her morning train.

  • As Kristina watched the train pull out of the station, she realized she would be late for work yet again.

The dependent clauses can also fall at the end of an independent clause as in these examples:

  • Kristina missed her morning train because she woke up late when her alarm malfunctioned.

  • Kristina realized she would be late for work yet again as she watched the train pull out of the station.

Here’s a complex sentence with two compound independent clauses and one dependent clause:

  • Kristina missed her morning train, and as she watched it pull out of the station, she realized she would be late for work yet again.

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