WEEK 3 GRAMMAR LESSON B: Complex Sentences
Review of simple and compound sentences
In Week 2, you learned about simple and compound sentences.
Remember that simple sentences have one grammatical subject and one verb. For example:
Ann played a game.
John and his sister watched the movie.
Compound sentences are two simple sentences joined with words like and, but, or so. The
connecting word goes before the second simple sentence. For example:
Ann played a game, and John read a book.
Ann decided to go outside, but John stayed inside the house.
Complex sentences
Complex sentences seem like two simple sentences that are connected with words like when,
if, because, although, while, as, where, before, after, and others. These words are called
subordinating conjunctions. Complex sentences are very useful to show how ideas are related
to each other.
Here are some examples of complex sentences:
1. You would know it if you saw it.
2. As Sylvie climbed slowly down the pine tree, the stranger was waking up at the farm.
3. When the cow heard Sylvie's voice calling her, she would hide among the trees.
4. He was smiling because he was sure that she had seen the white heron.
As you can see, each sentence has two subjects and two verbs. The subordinating conjunction
can be before the first subject (like in sentences 2 and 3) or the second subject (like in
sentences 1 and 4).
Complex sentences must have two parts: one part of the sentence has a subordinating
conjunction (If it rains . . .) and the other part of the sentence does not (. . . we stay inside and
play games).
If the two parts of the sentence are separated, you will have an incomplete sentence and a
simple sentence. It is good to include a mix of simple, compound, and complex sentences in
your story, but incomplete sentences are a mistake.
Compare these incomplete, simple and complex sentences:
Incomplete
Simple
Complex
When it is sunny.
We like to eat in the
When it is sunny, we like to eat in the
garden. OR We like to eat in the garden
garden.
when it is sunny.
Because it was
We stayed inside the
Because it was raining, we stayed
inside. OR We stayed inside because it was
raining.
house.
raining.
If it rains, we play games inside. OR We play
If it rains.
We play games inside.
games inside if it rains.
When you create complex sentences, always include both parts of the sentence like in the
examples above.
This is a program of the University of Oregon, College of Arts and Sciences, American English Institute.
Copyright 2016 University of Oregon. All rights reserved.
Week 3 Grammar Lesson B: Complex Sentences
Page 1 of 1