Frequently what we call a sentence fragment is really one sentence broken into two parts. As we write, we come to what seems like a natural ending. Since it seems like a natural ending, we might be tempted to put a period there, even though there is still more of the sentence to come. Then we go ahead and add the rest of the sentence and put another period at the end of that group of words. Look at the following, for example:
He looked everywhere for the missing document, in his secretary's desk, in the filing cabinet, in his brief case, even under the carpet.
The first part could be a sentence by itself. It has a subject and a verb, and it makes a complete statement:
He looked everywhere for the missing document.
Some people might feel that the original sentence is too long, and it should be broken into two sentences. The first part would be a correct sentence. The rest of it, however, would not be a sentence. It is just a series of prepositional phrases.
Here are some more examples of sentences that follow that same pattern. The first part of each one could be a sentence by itself, but if it were written as a separate sentence, the part that comes after the first comma would not express a complete thought. It would be a series of phrases, a fragment.
I decided to look for a better job, one with good pay and benefits.
I have to do everything around here, answer the phone, get out the mail, and run errands for my boss.
There are a lot of problems with this job, such as the hours, the pay, and the working conditions.
It looks like a verb, but is it really?
Every sentence needs a verb, but sometimes we have something that looks like a verb but is not. For example, we might have a present participle (a word that ends with -ing, like hoping). A present participle can be part of of verb, but it can't be a verb by itself; that is, without a helping verb. For example, here are some sentence fragments that I got from some of my students' papers. They all have a present participle, but none of them has a verb.
Wondering how it would all come out.
The job getting to me more and more all the time.
All the time thinking what a mistake he had made.
These statements are incomplete and unclear. We don't know from reading them what direction the flow of thought is supposed to go. In the first statement, for example, "wondering" could be intended as part of the verb.
He was wondering how it would all come out.
It could as easily be intended as part of a phrase.
Wondering how it would all come out, he made his choice.
Dependent Clauses as Fragments
A third form of sentence fragment occurs when when dependent clause is written as a separate sentence. (See more about dependent clauses under complex sentences.)Here is an example:
If you want to succeed in this company. You will learn to follow the rules.
"If you want to succeed in this company" has a subject and a verb, but it isn't a complete thought. It should be followed by a comma instead of a period.