The Comma

Chris Lele
Lesson by Chris Lele
Magoosh Expert
Learn More About Magoosh SAT
Commas on the SAT are all about clauses or comma splices or parallelism. That's usually where you will see them. Now, if you haven't gone over those things I recommend going to the clauses and the conjunction lessons first because it's gonna make a lot more sense how commas are used once you've seen those videos. So I assume you've done that but if not, I'll make sure to explain as much as possible.

There are lists such as thing a, thing b, and thing c. Those lists should be separated by a comma. That is, here's thing a. Here's thing b, and here's thing c. Comma should separate thing a from b, and thing b from c. So far, so good.

Now, independent clause is another way of saying complete sentence. If there are two complete sentences, you can use a comma and a conjunction, and that should be a coordinating conjunction also know as the FANBOYS. Again, go back to that lesson video if you're not sure what the heck I'm talking about. But anyway, as far commas go, you can separate sentences, independent clauses with a comma and a coordinating conjunction.

What else? Though I like the sense of power that comes with a sports car, I prefer cars that receive good gas mileage. Subordinate clause is not a complete sentence, it's also known as a dependent clause. It begins here with what is called a subordinating conjunction.

You don't have to know these terms, just know that, though I like the sense of power that comes with a sports car period, is wrong. That is not a complete sentence. You need a comma to separate it from the complete sentence. I prefer cars that receive good gas mileage. Okay. Moving on.

Which. Which starts off an adjective clause. The adjective clause describes that which comes right next to the which. It doesn't describe the subject of the sentence, he. That would be weird. He is driving a Tesla, which is an electric car.

Sometimes you can also just forget the which and say, he is driving a Tesla, an electric car capable of decent performance. You don't always need the which is, especially if you already have a long adjective clause. You will also see commas in appositives. So if we wanna describe someone specific, James, and we want to talk about something about James that's not really super important.

Just kind of like a random fact, we want to set that off by commas. James, who is coming over for dinner tonight, just got back from South America. We see this typically with famous people when we're describing them. Like, Mahatma Ghandi, who lead India to liberation against the British, was able to fight for justice, that kind of thing. Here though I'm just giving you generic people like Nancy.

The fact that she's captain of the soccer team isn't that important, just dropping that in there. What's important is she's studying abroad in Madrid, maybe she'll play soccer there who knows? Okay those are call appositives, again you don't have to know this terminology just how commas are used and how they're not used.

They're also used in what are called essential clauses, which differ from the which clauses that we saw just a second ago and the appositives. How? Well I'll tell you, first off let's look at the sentence. I'm going to choose a college that is on the East Coast. This is correct.

Notice I didn't say choose a college, which is on the East Coast. That's implying that there is just one college in the United States and that one college is on the East Coast. I want to talk about a specific college, I'm going to narrow down all the possible colleges or at least some of them and say a college that is on the East Coast. A specific college out of all the colleges, one that is on the East Coast.

You would not use a comma there, that is incorrect. Sometimes the SAT will test for that, so be careful. Also, we have a correct sentence. He is the type of person who. Why did I even put this in here? Well we talked about John or whoever it was in the previous slide.

We said comma and then we described that person. Here though, we're talking about a specific type of person. He's the type of person. Which type of person? And so you want to make sure not to put comma who, but just who. No comma there.

And by the way you don't want to put that either. That's another trick they use. People, that is human beings should always be described by who, but here we are dealing of course with commas. And so we want to make sure that if there is a specific person, he is a type of person, which specific person you do not wanna put comma who.

If you did, he's the type of person comma who, you're describing all types of people, but again, he has a specific type. Now, I think that is pretty confusing and I just wanna note that I don't think that SAT's ever gonna do that, but if you had a question then the difference between these two is this one is correct because it's a specific person and this one is wrong. Because you aren't describing all types of people.

Okay, I'm gonna do a little quiz because I think this can get a little bit confusing. Number one, the man who lives at 1143 Water Lane complained to the city officials about the noise. Is this correct or not? Basically I'm asking, should I put commas here? Or not.

If I put commas there, I am implying that the man, there is one man. I am the man, and I live at 1143 Water Lane. That's absurd. It's a very specific man, so when specific, get rid of the commas. They call that an essential clause, that's why I have that up here, but you know what?

You can just call the back clause. So we wanna get rid of those commas, and this is absolutely fine. What about number two? My biological father who still lives with us says we are too noisy at night. Is this right or wrong? So think about it again.

Here we have, is there one man? If there are many men, which of course there are, then you do not want commas. Does this person have one biological father? Yes, you can't say, oh my biological father. Let me now tell you the specific biological father. That would be weird.

You only have one. Therefore you wanna set that off with commas. My biological father, who still lives with us, comma. There's that appositive because there's only one biological father that this person could possibly have. Again this probably is not gonna really be tested on the SAT too much but I think this is so helpful in general with essay writing and that will help you on the SAT if you decide to do the essay.

What we wanna focus though is the interrupters and here we have some interrupters. You probably wanna ask, what is an interrupter? Well, let's have a look. SUVs are not as many assume. That is an interrupter.

Meaning it's set off by commas and I could totally get rid of it just like those appositives and not lose the flow. SUVs are not safe vehicles to drive. But someone wants to drop in a little opinion of theirs. And that opinion is the interrupter. SUVs are not and let me tell you how many, how often people are wrong comma safe vehicles drive since they blah blah blah.

That is the idea of an interrupter. Here's another one. I was wondering, indeed I often wonder, just what you were up to with that unruly neighbor. Again set off by commas. Not that common but I have seen this on the SAT where a correct answer choice would drop an interrupter in there.

People think it's weird and choose something else. Okay, final thing to talk about is comma splices. One of SATs favorite tricks. We're talking about using commas. Well sometimes you use them, the SAT uses them and they're incorrect. The car was expensive, it was equipped with luxury seats.

This is a comma splice, why? Take a second, read it. You should answer, it is a comma splice because it is combining two independent clauses. These are both sentences, therefore it should be a comma and a conjunction or a semi-colon or simply a period.

There you really have the uses of commas as well as the misuses of commas on the SAT. I would go through the actual passages in and start practicing getting a sense for commas. If something is a little bit off and you're just uncertain, than I would watch this video again and read any related blog posts on commas.

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