Grammatical Sentences

First, lets define sentence: a sentence is a group of words that has a subject and a verb and can stand alone or be independent, making a complete thought .
Example: It is snowing.

Now, lets define clause: many clauses resemble sentences in structure (having a subject and a verb) because a sentence is a main clause-- an independent clause . However, a clause that cannot stand alone or make a complete thought is dependent and must rely on a nearby sentence, or another sentence for support.
Example: Because it is snowing. Dependent

Notice that many fragments would be correct responses to questions, and would be fine to punctuate as complete thoughts in dialogue.
Example: Why is the teacher absent? Because it is snowing.

Dependent clauses by themselves are fragments of thoughts. Thus, sentence fragments may pretend to be sentences, being instead clauses with subjects and verbs that still cannot stand alone. All sentence fragments will be in italics on this handout.
Dependent clauses usually have a word or words at the beginning that identify them as dependent. These words may be adjectives, adverbs or nouns.
The house that Jack built . (Adjective--answers which one? what kind of?)
The house that Jack built was the strange one on the corner.
If only we had more time. (Adverb--modifies verb)
If only we had more time , we could have written better papers.
Where the action is. (Noun--subjects, objects or complements--to go with or complete)
I want to be where the action is . Where the action is is where I want to be.
In the second sentence above, the close repetition of the word is may be bothersome, but it is grammatically correct. No comma is needed between the two words.

A sentence fragment may also just be a fragment of a thought that lacks a subject, a verb, or both. Fragments commonly punctuated as sentences usually contain prepositions (on, for, with). Example: Where are the keys? On the table. Examples are often fragments.
They may also contain participles, gerunds or infinitives (verbal phrases ) that may at first look like verbs, but many are subjects, and these may function in other ways.
Participles : (present and past) Being a teacher. Put on a pedestal.
Gerunds : (present--ending in ing) Growing strong and tall. Volunteering to help.
playing music. Studying for her finals.
Infinitives : (beginning with to be) To be a good mother. To read the newspaper. To understand. To be a student.
Verbal phrases can move around in a sentence without changing in structure.
Studying for her finals put her to sleep. (Subject)
She was studying for her finals. (Verb)
Studying for her finals , she had no time to waste. (Modifier)

Appositives are often punctuated as complete sentences. Appositives describe or rename the noun or pronoun of a sentence, and they need to remain near this noun or pronoun in order to make complete sense.
My uncle can do anything. A jack of all trades . He built our deck, fixed our car, cooked our supper, and instructed our daughter in piano.
A jack of all trades, my uncle can do anything.
My uncle, a jack of all trades , can do anything.
My uncle can do anything. A jack of all trades , he built our deck....

Understood subjects can also confuse people. This is acceptable: Close the door.
Understated subjects are also confusing sometimes. Pronouns can be vague.
My sister went to her doctor for a flu shot. She had the flu.
Who is the she in the second sentence? The sister or the doctor?
I just gave you an example of an understated verb. I asked a question without repeating the verb of the previous sentence. Is it the sister or is it the doctor? Understated verbs can also be confusing. You have to think of purpose and audience at all times.

So, how do you fix a fragment?
Give it what it is missing, if it is missing something.
Take away what makes it dependent, or link it to a nearby sentence in a grammatically correct way. Check for sentence complete ness. Think of purpose and audience.
Fragments can be used correctly: for emphasis, to answer questions, as transitions, exclamations, in advertising, to get attention. Do use them sparingly, if you use them.
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Run-ons : Comma Splices and Fused Sentences.
A comma splice is two (or more) complete thoughts (sentences--main or independent clauses) that have been joined incorrectly with a comma .
A fused sentence is two (or more) complete thoughts (sentences--main or independent clauses) that have been joined incorrectly with no punctuation at all between them .

These can be fixed by (taking out the comma in a comma splice and) inserting a period
after the first sentence and capitalizing the first letter of the next sentence.

You can join two sentences correctly in many ways.
You wanted the material to go together, or it wouldnt have been joined to begin with.
You could make one sentence dependent, and subordinate to the other.
The window was open the rain came pouring in. Fused
Because the window was open, the rain came pouring in. Correct

One of the best ways to join two sentences correctly is to use a comma and the appropriate coordinating conjunction.
Make sure your intention is matched.
For gives reason, for example, and and means in addition.
It is easy to remember the coordinating conjunctions by remembering this word: FANBOYS :          F OR A ND N OR B UT O R Y ET S O
Use appropriate punctuation to join:
, coordinating conjunction (see above FANBOYS )
;         a semicolon (between two closely related sentences)
; conjunctive adverb          a semicolon and a conjunctive adverb--like however
:         a colon
--          a dash--although this is seen as more casual or poetic.

Two suggestions above call for the use of semicolons. Many people are afraid to use these, or do not know how to use them. There are only two ways to use a semicolon.
Semicolons only belong between two closely related sentences or in place of commas in a list where more commas would be confusing. Examples follow.

It is raining ; however, I do not want to close the window. Correct.
It is raining. I do not, however ; want to close the window. Incorrect.

The material on each side of the semicolon must be a complete sentence,
unless the semicolon is in a list.

The people who will go to the party are: my father, Jesse, my husband, Joseph, my cousin, James, my mother, Gladys, my sister, Ruby, my cousin, Jane, and my two kids, Joan and Jenny.

How many people are going to the party? 14...or 8?

Now look:
The people who will go to the party are: my father, Jesse; my husband, Joseph; my cousin, James; my mother, Gladys; my sister, Ruby; my cousin, Jane; and my two kids, Joan and Jenny.