Missing Comma After Introductory Element

It’s important to remember that introductory words and phrases—any words or phrases that come before the main clause in a sentence—should be set off with a comma. Here is an example of a sentence that does not include the required comma and then the correction:

• (Missing Comma) In case you were wondering I never allow myself to be exposed to direct sunlight unless I have my scarf, my sunglasses, and a large umbrella.
• In case you were wondering, I never allow myself to be exposed to direct sunlight unless I have my scarf, my sunglasses, and a large umbrella.

Unnecessary Comma

When beginning writers are first learning comma rules, they have a tendency to forget that the rules all depend upon the situation. So, when you learn to place a comma before a coordinating conjunction like and, but, or so when you join two independent clauses, you might have an urge to place a comma before and, but, or so every time you use these words. You should avoid this urge!

Just because you need to use commas with coordinating conjunctions sometimes doesn’t mean you’ll use them all the time.

• I have a wide variety of supernatural powers, but wish I had the power to go out in the daylight.

In this example, you don’t need a comma before the but because you aren’t combining two independent clauses. Here is a corrected version of the sentence:

• I have a wide variety of supernatural powers but wish I had the power to go out in the daylight.

You should also be careful that you aren’t using commas unnecessarily around information that is essential to the sentence. The comma rule is that non-essential information should be set off with commas, but essential information should not.

• I find that a little fear is the best seasoning, for my food, so I often sneak up on my husband while he cooks and frighten him.

In this example, for my food is not extra information that should be set off with commas. But, you do need a comma before the so to separate the two independent clauses. Here is a corrected version of the sentence:

• I find that a little fear is the best seasoning for my food, so I often sneak up on my husband while he cooks and frighten him.

Missing Comma with Nonrestrictive Element

Just as you should not put commas around essential or restrictive information in a sentence, you must remember to put commas around information that is non-essential or nonrestrictive.

If the information is not essential to the meaning of the sentence, you need to be sure to set it off with commas. Here is an example of a sentence without proper commas around the nonrestrictive element:

• Moving into a cave especially one that is already occupied is not a decision one should make without considerable forethought.

Here is the corrected version:

• Moving into a cave, especially one that is already occupied, is not a decision one should make without considerable forethought.

If you have trouble deciding whether or not you need commas around “extra” information in your sentences, be sure to review the comma rules in the Punctuation area of the Excelsior OWL.

Missing Comma in Compound Sentence

When you join two independent clauses (complete sentences) with a coordinating conjunction (and, but, or, nor, for, so, yet—also known as the FANBOYS), you must place a comma before the coordinating conjunction.

The rule is very clear, here. The comma before the coordinating conjunction works with the coordinating conjunction to help make a proper boundary between the two independent clauses.

• I understand that vampires and ghouls need love but I don’t think they really understand just how attached I am to my vital, bodily fluids.

In this example, the sentence is missing the comma before the but because the but joins two complete thoughts. Leaving out this necessary comma creates an error because you have two sentences connected without a proper boundary between those sentences.

Here is a correction for the sentence:

• I understand that vampires and ghouls need love, but I don’t think they really understand just how attached I am to my vital, bodily fluids.

Comma Splice

Many students think a comma splice is just any kind of comma error, but a comma splice is a very specific type of comma error.

A comma splice occurs when you use a comma to separate two independent clauses. A comma is not strong enough to perform this function, which causes the problem. It’s important to remember to use proper punctuation to separate your independent clauses; otherwise, you end up with a sentence like this:

• He promised me, if I didn’t report him, he would never do it again, however, the next night, he was back, playing his bagpipes under my balcony.

Here, you should notice the only comma error is the one between again and however. The reason this is a comma splice is because the actually begins a new sentence or independent clause, but there is not a proper boundary between these two sentences. Here is how the sentence could be corrected:

• He promised me, if I didn’t report him, he would never do it again; however, the next night, he was back, playing his bagpipes under my balcony.

Missing or Misused Quotation Marks

​​Using quotation marks correctly can be a little tricky, especially when you need to use other types of punctuation with them. Mechanical errors related to quotation marks makes the most-common error list because beginning writers often forget that commas and periods go inside the quotation marks. Here is an example:

• “When you are courting a nice girl, an hour seems like a second. When you sit on a red-hot cinder, a second seems like an hour. That’s relativity”, said Einstein.

In this case, the comma placed outside the quotation marks is incorrect. The comma should be placed inside the quotation marks like this:

• “When you are courting a nice girl, an hour seems like a second. When you sit on a red-hot cinder, a second seems like an hour. That’s relativity,” said Einstein.

It’s important to note, however, that not all punctuation automatically goes inside the quotation marks. Question marks are a little trickier. If the only part in quotations is a question, then the question mark should go inside the quotation marks; otherwise, the question mark actually goes outside of the quotation marks. Tricky for sure!

Also, students often forget that titles of shorter works, like essays and short stories, should be placed inside quotation marks. Longer works, like books and magazines, should be placed in italics.

• I read the essay “The Marginal World” by Rachel Carson in the book Best American Essays of the Century.

Apostrophe Errors

Apostrophes give many writers a lot of trouble. Sometimes, you might be tempted to put an apostrophe where it does not belong, such as when you are simply making a word plural. Other times, you need to make a word possessive, but you might forget to use the apostrophe.

Then, of course, there is that whole its / it’s thing that confuses most everyone.

Remember, the rule is to use an apostrophe when you need to show possession or ownership. The exception is with its.

Its shows ownership because it’s means it is. So, it’s like it’s is already taken, so its gets to be an ownership exception. To make sure you are using It’s correctly, just say it is when you read it. If it makes sense, you’re fine. However, if you’re trying to show ownership, and it is would not work in the sentence, you need to make the change to its.

For more information on the apostrophe, be sure to check out the Apostrophe section in the Punctuation area of Grammar Essentials (or if you just need to brush up your skills, visit the Apostrophe Refresher). Otherwise, you might end up with a sentence like this:

• Its abundantly clear, to me, that creature’s of the night are just misunderstood and misguided beings who sometimes err in judgment and eat their neighbors’ as well as their neighbors families.

And, you would want a sentence like this:

• It’s abundantly clear, to me, that creatures of the night are just misunderstood and misguided beings who sometimes err in judgment and eat their neighbors as well as their neighbors’ families.

Hyphenation Errors

Hyphens can be a little tricky, but they are important. For example, there is a world of difference between a dirty-movie theater and a dirty movie theater. You probably wouldn’t want to go to either one, but there is a big difference between the two.

Hyphens are tricky because location is also very important in determining whether or not you need to hyphenate words.

The rule is pretty clear, however. Most of us just need a reminder. When you have two or more words that modify or describe a noun that follows, you should hyphenate those words. You should not hyphenate the same words if they come after the noun.

Take a look at the following example where hyphenation errors exist in several places:

• It was clear that, after his two dollar hair-cut, Bertram began suffering from low self esteem.

Here is what the correction should look like:

• It was clear that, after his two-dollar haircut, Bertram began suffering from low self-esteem.