Punctuation

Sentence Ending Punctuation

Periods, exclamation points, and question marks are sentence-final punctuation. You should not have a space after the last letter of a word before one of these punctuation marks. You should have one space after these punctuation marks before the first letter of the next word.

Period .

Used to end most declarative sentences

Exclamation point

!

Used to end declarative sentences with great emotion

Question mark

?

Used at the end of a question

Listing Punctuation

A colon (:) is used to introduce a list if there is a complete sentence before the list.

There are two main types of books: fiction and nonfiction.

When you finish your essay, you should check it for the four features of good writing: organization, development, accuracy, and originality.

Commas (,) and semicolons (;) are used for separating items in a list.

1.Commas are used to separate items in a list without punctuation. If several adjectives are listed to describe a noun, a comma separates them.

I have lived in California, Utah, and Texas.

The beautiful, new building was finished this summer..

2. Semicolons are used to separate items in a list when the items contain commas. When we write cities and states in English, a comma always separates the city and the state.

I have lived in San Diego, California; Provo, Utah; and Houston, Texas.

*If we used commas in a list that already has commas, it would be very confusing.

I have lived in San Diego, California, Provo, Utah, and Houston, Texas. (Incorrect)

1 Exercise: Revise listing punctuation.

Revise the sentences that are written incorrectly. 

  1. Interesting buildings on BYU campus: The Wilkinson Center, the Museum of Art, and the Fine Arts Center. 
  2. If you have clear organization, you have a clear, controlling thesis, specific, connected topic sentences, and a logical flow between your ideas. 
  3. April, June, September, and November each have 30 days. 
  4. We will write three major essays this semester: a problem/solution essay, a comparison essay, and a process essay. 
  5. New students attend an informative helpful orientation at the beginning of the semester. 

Sentence Linking Punctuation

Comma + Coordinating Conjunction You can link two independent clauses (complete sentences) together with a comma if you also use a coordinating conjunction. These conjunctions are sometimes referred to as FANBOYS (for, and, nor, but, or, yet, so).

There are many ways students use commas, but not all of those ways are correct.

Notice that there are two complete sentences:

There are many ways students use commas.

Not all of those ways are correct.

**Remember that you only need a comma if you are joining two COMPLETE sentences together.

I need to print my essay tonight, and ask my study buddy to give me some feedback. (Incorrect)

I need to print my essay tonight and ask my study buddy to give me some feedback. (Correct)

Semicolon

Another way to link two complete sentences is by using a semicolon.

There are many ways students use commas; not all of those ways are correct.

Notice that there are two complete sentences again:

There are many ways students use commas.

Not all of those ways are correct.

A comma combined with a coordinating conjunction does the same thing in this situation, but a semicolon shows a stronger connection between the sentences. Writing this type of sentence can also add variety to your writing. If you use a semicolon, NO conjunction is necessary.

2 Exercise: Revise linking punctuation.

Revise the sentences that are written incorrectly. If there are multiple ways to correct the sentence, write all of the possible corrections. 

  1. Personality tests can tell you a lot about a person, but they aren’t a perfect measure of what people are really like. 
  2. BYU has lots of fun activities for students, you will never be bored on the weekends. 
  3. Amazon is one of the most popular websites for online shopping; and you can find a wide variety of products that ship quickly to your home. 
  4. Electricity was one of the most important inventions in the nineteenth century and it led to other important inventions. 
  5. The United States fought a revolutionary war against England and won their independence. 

Variety and Avoiding Linking Errors

Variety in sentence length is important for your writing. Some sentences should be short, while some can be linked to other sentences to create variety.

When you link independent clauses, you need to be careful to avoid run-on sentences.

A run-on sentence either has no punctuation between independent clauses, or splices two independent clauses together by only using a comma. (This type of run-on sentence is called a “comma splice sentence”.)

He will help her prepare for the TOEFL and she will practice every day. (Incorrect)

He will help her prepare for the TOEFL, she will practice every day. (Incorrect)

He will help her prepare for the TOEFL, and she will practice every day. (Correct)

He will help her prepare for the TOEFL; she will practice every day. (Correct)

He will help her prepare for the TOEFL. She will practice every day. (Correct)

Remember that even if you are correctly linking independent clauses together, do not link too many together because it will make your writing harder to read.

3 Exercise: Revise run-on sentences.

Revise the punctuation in the student paragraph. 

        Parents do not control what their children do; children’s behavior is affected more by television, movies, and other influences from outside the home, this is a terrible thing that sociologists have noticed, but fortunately, parents are still interested in trying to teach their children, parents should teach their children about good behaviors and parents will see improvements in the behavior of their children.

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