Want to improve your writing? Well, there are some common errors that you might want to look for as your revise and edit your writing. Here's the first one:  

Error #1: Run-on Sentence or Comma Splice
A run-on sentence is a sentence that joins two independent clauses without punctuation or the appropriate conjunction. A comma splice is similar to a run-on sentence, but it uses a comma to join two clauses that have no appropriate conjunction.
Fixing a run-on sentence or a comma splice can be accomplished in one of five different ways:

• Separate the clauses into two sentences.
• Replace the comma with a semi-colon.
• Replace the comma with a coordinating conjunction--and, but, for, yet, nor, so, or.
• Replace the comma with a subordinating conjunction--after, although, before, unless, as, because, even though, if, since, until, when, while.
• Replace the comma with a semi-colon and transitional word--however, moreover, on the other hand, nevertheless, instead, also, therefore, consequently, otherwise, as a result.

For example:

• Incorrect: Rachel is very smart, she began reading when she was three years old.
• Correct: Rachel is very smart. She began reading when she was three years old.
• Correct: Rachel is very smart; she began reading when she was three years old.
• Correct: Rachel is very smart, for she began reading when she was three years old.
• Correct: Because Rachel is very smart, she began reading when she was three years old.
• Correct: Rachel is very smart; as a result, she began reading when she was three years old.

Read more at 18 Most Common Grammar Mistakes 

Comma splice errors are very common mistakes, but they can be easily avoided. How?

First, anytime you use a comma in your writing, you should be ask yourself, "Why?" In other words, think about why you are using that comma. What is the rule for its usage?

Second, if you are editing or reviewing your writing, look for commas found in the middle of a sentence. When you find one, review the sentence carefully to see if you have an independent (or main) clause on either side of the comma. If you have an independent clause on both sides, and you do not have a conjunction joining them (like: and, but, or, nor, for,so), then you have yourself a genuine comma slice error. 

It may look like this:  I went to the store this morning, I bought some milk. 

A careful review of the sentence above should result in the conclusion that there are two independent clauses presented, one on either side of the comma. This is a comma splice error. 

To read more about comma splice errors, click here. 

To practice identifying comma splice errors, click on the links below. 

Comma Splice Practice #1
Comma Splice Practice #2
Comma Splice Practice #3

Click on the links below to practice using "the comma" correctly: 

• Comma Quiz 1
• Comma Quiz 2
• More comma quizzes

One of the most challenging things you will face when trying to learn English is mastering the comma.

When do I use a comma? Where should I put it in my sentence? Is it the same as a period? 
To answer  your questions, I invite you to read through this presentation below. 

Click here.  

You will be directed to a screen that looks like this:  
 

Click on the Powerpoint Presentation (next to the words Media File).  It says:  Conquering the Comma PowerPoint Presentation. 

Read through the presentation completely. We will discuss it as a class and then practice applying the rules.