What You Need to Know

Key Concept Diagram

Simple sentences have one main clause (e.g. The dog barked.)

Compound sentences join two main clauses with a coordinating conjunction (e.g. The dog barked and the cat ran.)

Complex sentences have a main clause and a subordinate clause (e.g. The dog barked because it was scared.)

Varying sentence length creates rhythm: short sentences add emphasis; longer sentences build detail

Key Vocabulary

Simple sentence

A sentence with one subject and one predicate (one main clause)

Compound sentence

Two main clauses joined by a coordinating conjunction such as and, but, or so

Complex sentence

A sentence with a main clause and at least one subordinate (dependent) clause

Coordinating conjunction

A joining word that connects two main clauses: for, and, nor, but, or, yet, so (FANBOYS)

Knowledge Check

Select the correct answer for each question. Click "Check Answer" to see if you are right.

Question 1

Which sentence is a simple sentence?

The rain fell and the river rose. Although it was cold, she went outside. He read a book, but she watched TV. The sun set.

Question 2

Which word makes this a compound sentence? "I wanted to swim ___ the pool was closed."

but although because when

Question 3

Why should writers vary their sentence lengths?

Longer sentences are always better Varying length creates rhythm and makes writing more engaging Short sentences should never be used All sentences should be the same length for clarity

Sentence Variety and Structure