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Author: Martina Shabram

Identify and correct errors in comma usage.

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Hello, students. My name is Dr. Martina Shabram. And I will be your instructor for today's lesson. I'm genuinely excited to teach you these concepts, So let's get started.

What's today's lesson? Well, we're going to work on punctuation. And specifically, we'll learn about how commas work in a variety of sentence types and constructions. And we'll learn how to identify mistakes in comma use.

A comma is a punctuation symbol used in multiple ways to indicate a pause or a particular organization. Commas are one of the most useful tools. Correctly used, they will make sentences clearer and improve your organization.

Incorrect use, however, can cause confusing sentences or even create unintended meanings. For example, without commas to separate the items on this list, it seems that this speaker eats crafts and pets. So commas helps separate and organize the relationship between these words and phrases, as they will, in many kinds of sentences.

Therefore, it's not useful as a writer to just distribute them randomly in our writing, as some authors do. So unless you know that a comma belongs in a sentence because there is a rule indicating so, it's better to leave the comma out. In the above example, your reader will probably assume that you don't eat pets and crafts. But that instead, you love eating, crafting, and pets. A comma where it doesn't belong can create more confusion than a comma that's missing altogether.

But the best thing to do is to use commas appropriately wherever they belong. So let's learn some rules, then, about comma use, so that we can harness the power of the comma. In a series or a list of items, commas are used to separate each item. When we have three or more entries into the list, then we have a series. Just two and it's only a pair.

For example, so we'd use a comma after the first item, Nashville, and then after each other item in the list, culminating in the final comma, which should go before the and or the or that will round out the list. Nashville, comma, Atlanta, comma, and New Orleans.

The same holds true when your series features items that are phrases, not singular words such as. Here, each phrase serves as its own entry in the list. Commas follow particular rules in particular sentence constructions, as well, and are very important in both compound and complex sentences.

If you recall, a complex sentence it is a sentence that combines at least one dependent clause with at least one independent clause. And a compound sentence is a sentence that combines two or more independent clauses. In both types of sentences, commas separate these clauses.

In compound sentences that are combined using coordinating conjunctions, the comma is placed before that coordinating conjunction, such as, the day is cold, but it's not snowing. Or I'm going to stay inside so I won't need my heavy coat.

See how the comma in each of those sentences comes before the coordinating conjunction? In complex sentences, the comma may separate the independent and dependent clause. But this will only happen when the dependent clause comes first, not if the independent clause is first.

A complex sentence where the independent clause comes first will look like this. "We can't go skiing since it's not snowing." But if we were to reverse the order and put the dependent clause first, then we would need a comma to separate the two. "Since it's not snowing, we can't go skiing." We might also write, "unless it starts snowing soon, we won't be skiing tomorrow."

Notice in these sentences how the comma separates the dependent first clause and links it to the independent clause that comes second. So let's practice. Here's a sentence for you. Is this compound or complex? This is a compound. So where would you add the comma in this sentence? Before the coordinating conjunction, here.

Another place that we need commas is in introductory phrases. In these constructions, the comma sets the introductory phrase off, separating it from the sentence it's going to introduce. That might look like this. "On snowy days, it's common for many people to work from home."

So let's notice here where the comma is. It comes at the end of the introductory phrase, on snowy days, and before the rest of the sentence. When we read this out loud, think about where we would naturally pause. I wouldn't say, "on snowy days it's, common for many people to work from home," or "on, snowy days it's common for many people to work from home." Those just don't feel right.

So often when we're looking for commas, we can read our sentences aloud and see where in natural conversational speech we might pause. That's usually a good clue that a comma belongs there. So why don't you try with this one. Pause and read it aloud and then decide where you would put your comma in. You probably said, "after a heavy snow, the roads may be dangerous," and therefore put a comma here.

So let's try spotting some commas in a short paragraph. Go ahead and pause to read this little paragraph. And then press play when you're done. So what do we see? Are we missing any commas? Yes, we are. We're missing one here.

Well, how do we know? When I read this aloud, I find that I pause here. And if we look at the sentence structure afterwards, we can realize that if skiing is too intimidating is a dependent clause subordinate to the independent clause, snowshoeing can be fun. And since that dependent clause comes first, we remember the rule that there needs to be a comma separating the two.

Did you find any extra commas? Let's look at that first sentence. Read it out loud with me. "Ski resorts can be ideal locations for a family vacation." I wouldn't naturally pause there. So by reading aloud, I caught an extra comma.

Now there are some other places that you might find commas. Commas surround interruptions in sentences. For example, my sisters, none of whom have ever skied before, are planning a trip to Tahoe. Or, the weather report, which is usually correct, indicates that we're going to see a lot of snow. It's like a little interruption to the rest of the sentence and so it needs to be separated by commas to indicate that it's its own unit of meaning.

Similarly, commas set off dialogue or quotations, again, indicating that the words quoted or spoken are separate from the rest of the words. We'll also see commas in dates and geographic names. In the US, we indicate dates like this. The comma separates the month and day from the year. In geography, we do the same to separate the city from the state it's in.

Now sometimes, you might even find a comma in a place where you can't think of any universal rule that makes it need to go there. And yet, that comma might be necessary for clarity. That's OK. Sometimes, those commas are just necessary. And you'll often find that you catch comma errors when you're in the proofreading stage of the writing process. So as you proofread, be sure to read out loud.

So what did we learn today? Well, we got familiar with the comma, learning about the rules for its use in lists, compound and complex sentences, introductory phrases, and all the other miscellaneous places that commas are needed to separate units of meaning within sentences.

Well, students, I hope you had as much fun as I did. Thank you.

Terms to Know

A punctuation symbol used in multiple ways to indicate a pause or a particular organization.

Complex Sentence

A sentence that combines at least one dependent clause with at least one independent clause.

Compound Sentence

A sentence that combines two or more independent clauses.