Also known as incomplete sentences, fragments are generally frowned on in the English language. Exceptions exist, and I’ll get to them later.
Defining sentence fragments
First, let’s define a sentence fragment. It’s a sentence that doesn’t have a subject and verb of its own.
“I thought about writing this article.”
“I” is the subject, and “thought” is the verb.
“Celine and Michael became depressed when they realized they couldn’t find their car.”
Both “Celine” and “Michael” are subjects. “Became” is the verb.
This sentence, however, has more to it.
“when they realized they couldn’t find their car.”
You might be thinking, “What about ‘they’? Isn’t that a subject, and isn’t ‘realized’ a verb?”
Yes, but the phrase makes no sense on its own. Its meaning depends on the previous part of the sentence, which makes it a dependent clause.
“Celine and Michael became depressed” is a sentence on its own. It says what happened. It’s not very informative, but it’s grammatically complete. That makes it an independent clause.
You can quickly spot a dependent clause by the conjunction that begins it: after, though, although, because, since, when, whether, etc.
Here are a few more examples.
“Why are you rooting through your bag?”
“Because I’m looking for the coupon I wanted to give you.”
People talk this way all the time, and it sounds natural. It wouldn’t be wrong to use it in written dialogue, sparingly. You could easily make it a complete sentence, though.
“I’m looking for the coupon I wanted to give you.” “Because” isn’t necessary.
The Sliding Scale of Complete/Incomplete Sentences
The basic principle of whether or not to use an incomplete sentence relates to how formal the writing is.
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We see that advertising copywriters thrive on sentence fragments.
This poetic form also has fragment fans.
Snow in my shoe
—Book of Haiku, Jack Kerouac
I see a lot of incomplete sentences in fiction.
“He looked out over the winter landscape. Snow drifts the height of a building. A sky hung with gray sheets.”
The paragraph could be revised as follows:
“He looked out over the winter landscape: snow drifts the height of a building, a sky hung with gray sheets.”
The first version, though, has a more desolate feeling to it.
In addition, as I mentioned earlier, incomplete sentences are acceptable in dialogue.
The key is sparing use. Otherwise, the prose reads in a choppy, disconcerting manner.
Can You Use Sentence Fragments in Non-fiction?
And why would you?
I just did, to show that you can.
I think that sometimes a writer wants to emphasize certain points. Imagine, for example, beginning an article on global warming like this:
This is your children’s future.
This can be catchy but should also be used sparingly. Otherwise, it runs the risk of choppy reading and also loses its dramatic impact.
In conclusion, you may deliberately use sentence fragments to best advantage. Don’t use them by mistake.