In your writing, there are 3 major problems that we commonly have to address as teachers/instructors/professors/etc. I want you to take the time to read about these. While we don't expect this to fix your issues instantly, we are hoping that you'll aim to make less of these mistakes in the future (especially on your papers, where these errors WILL be counted off for).
Comma Splice -- Commas are tricky because there are so many different ways you can use them, but one of the most common ways to use commas is to separate two main clauses that are connected by a coordinating conjunction. That just means that when you join two things that could be sentences on their own with a word such as “and,” “but,” or “or,” you need a comma before the conjunction:
Squiggly ran to the forest, and Aardvark chased the peeves.
Squiggly ran to the forest is a complete sentence, and Aardvark chased the peeves is also a complete sentence. To join them with a comma, you need the word “and” or some other coordinating conjunction. If you just put a comma between them, that's an error called a comma splice or a comma fault:
Squiggly ran to the forest, Aardvark chased the peeves. (wrong) The easiest way to remember how to check for a comma splice, is to read the sentence in your head. If it sounds like it could be two (or more) separate sentences, then it probably is. Here's another example: Sara obviously named that one, she was a sucker for those old “Happy Days” reruns. It should read:
Sara obviously named that one. She was a sucker for those old "Happy Days" reruns.
Now, be aware that sometimes making one sentence into two can make your writing sound choppy. There are other ways you can fix comma splices though, to take care of such an issue.. Such as using a coordinating conjunction (and, or, but, so, etc.): Aspen was too far away for us to drive there, we decided to fly. (incorrect)
Aspen was too far away for us to drive there, so we decided to fly.
You can also subordinate one clause to the other. This can prioritize the importance of each clause, which is sometimes very handy: Because Aspen was too far away for us to drive there, we decided to fly.
Now, there is one other way to fix Comma Splices, and that is a semicolon. However, I would suggest against using a semicolon, as often times they're unnecessary and used improperly. Also, you can conjunctive adverbs with the semicolon: Aspen was too far away for us to drive there; we decided to fly. (semicolon)
Aspen was too far away for us to drive there; instead, we decided to fly. (semicolon and conjunctive adverb)
Once again though, I'd like to stress not using a semicolon because of their erroneous nature. One of the other methods should suffice. Contact myself or Dr. Wilson if you need any help with these.
Common Mistakes in Writing: Run-on Sentences
The second mistakes we're going to cover, is the run-on sentence (also known as a fused sentence).
Run-on sentence--This is when you have two or more independent clauses without any kind of punctuation (as opposed to the incorrect comma splice, which uses a comma) separating them. There are many ways you can correct these: The new chancellor instituted several new procedures some were impractical. (wrong)
-By making two sentences:
The new chancellor instituted several new procedures. Some were impractical.
-By joining the two clauses with a semicolon, if they are closely related (I advise against this one): The new chancellor instituted several new procedures; some were impractical.
-By joining the two clauses with a semicolon followed by a conjunctive adverb (I also advise against this one): The new chancellor instituted several new procedures; however, some were impractical.
-By joining the two clauses with a comma and coordinating conjunction: The new chancellor instituted several new procedures, but some were impractical.