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SAT

Unit 11: Lesson 3

Writing: Grammar

Writing: End-of-sentence punctuation — Example 2

Watch David work through an SAT Writing: End-of-sentence punctuation question.

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  • blobby green style avatar for user joyce mougarbel
    can a colon unite a dependent and an independent clause ?
    (2 votes)
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    • piceratops ultimate style avatar for user Hecretary Bird
      A colon simply tells the reader to stop and take note of whatever follows the colon. This can be done when it introduces a list or quotation, such as in "Usnavi loves to eat salad, ice cream, and cranberries, but not all at once." You can also use colons to introduce an important phrase, like "Usnavi wasn't the brightest, but he did know one thing: he had to get to school by 8." Actually, there are cases where the colon would be between two independent clauses, but this is always when the second clause describes or explains the first, in accordance with normal colon rules. Take "Usnavi sprinted like a madman to reach the bus stop: he was horribly late for work." On the SAT, though, bridging independent clauses is left to the semicolon. If the words on the other side of the colon make a dependent clause, then you could say that it unites an independent and dependent clause. That might be tested on the SAT, but I doubt it.
      (9 votes)
  • mr pink red style avatar for user Adi
    Isn't their the subject as it is a pronoun and replaces Fresnel lenses.
    (2 votes)
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  • blobby green style avatar for user Neely598
    At , if a comma splice is ungrammatical, how is option C the best choice and not option A?
    (0 votes)
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  • leaf yellow style avatar for user Afaq Azim Mishwani
    the second sentence more seems to be dependent on the first one how actually you determined it as independent clause please give me tip
    (2 votes)
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  • blobby green style avatar for user cd81952
    If the question was "Which one is the best answer?", which one would be more grammatically correct than the other and why?
    (2 votes)
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  • stelly yellow style avatar for user Prajna Ray
    According to the current American English Grammar rules, do we put a comma before the 'and' while listing items? (example- cats, dogs, and rabbits OR cats, dogs and rabbits)
    (1 vote)
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    • female robot amelia style avatar for user Johanna
      The comma before the “and” (or another coordinating conjunction) in a list is called the Oxford comma, so I just browsed the Google results for “sat oxford comma”. By these, it seems the SAT always uses the Oxford comma in its own writing, but doesn’t really write questions on it because this grammatical rule is still debated. It seems that if you wanted to be cautious, you would want to use it, like: “cats, dogs, and rabbits”.

      Does this help?
      (1 vote)
  • blobby green style avatar for user ddgraham447
    This is a problem I have time and time again. Answer B creates the sentence: Their concentric rings amplify and concentrate light. HOW is this a sentence? How is it acceptable to write a sentence that is incomplete? Whose rings? How can you rely on the previous sentence to supply critical information. (I have a list of dozens of these from your grammar videos and they are driving me crazy).
    (1 vote)
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    • female robot amelia style avatar for user Johanna
      “Their concentric rings amplify and concentrate light” isn’t grammatically a fragment. It isn’t always the most helpful thing to think of a sentence as making sense or being a complete thought. To be a sentence (or an independent clause), something needs to have a subject and predicate, and it can’t leave out parts of any phrases it introduces. For example, you can’t just say, “I will drive to” because you don’t give the preposition “to” any object. “I will drive to school” works as a complete sentence, though.

      Nowhere in the requirements for a sentence is including the noun to which a pronoun refers (the pronoun’s antecedent).

      Let’s take your first sentence as an example: “This is a problem I have time and time again.“ It’s a complete sentence, even though we don’t know what the demonstrative pronoun “this” is out of context. Of course I can tell that “this” is sentences omitting pronouns’ antecedents, but that one sentence doesn’t tell me that. It’s still a sentence.

      Your first sentence also omits the antecedent of the pronoun “I”. Out of context, I’d have no clue who “I” is. Again, though, I can guess that “I” is in fact the Khan Academy learner “ddgraham447”.

      Basically, a sentence needs to include a subject and predicate, and it can’t leave any phrase or clause it introduces unfinished. A sentence does not need to include its pronouns’ antecedents, though.

      Does that help?
      (1 vote)
  • duskpin ultimate style avatar for user programmer
    Yet again, another question that will not be asked in the SAT...since these videos are definitely not being very helpful could someone possibly give me a detailed description of the different punctuations - and when which one is better over the rest?
    (1 vote)
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  • aqualine seed style avatar for user Asha Patterson
    What is the purpose of a semicolon and how does it differ from the purpose of a comma?
    (0 votes)
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    • duskpin seedling style avatar for user foooood!!!
      i think that a semicolon separates two main clauses. kind of like two sentences that are closely related. a comma would make both clauses one sentence and a full stop would make the clauses too separate. best to check it out though.
      (3 votes)

Video transcript

- [Instructor] So, let's take a look at these answers choices but before we do, let's talk about this word fresnel for a second. Because I was confused about it but my colleague, who has a long history in the theatre world, tells me that in the US, you don't say the s. You say fresnel, accent on the nel. Anyway. We are trying to figure out what piece of punctuation should go between purpose and their. Should it be purpose, semi-colon, their as it is in the sentence? Should it be purpose, period, capital T their? Should it be purpose, comma, their? Or should it be purpose, colon, their? Well, in order to figure out what piece of punctuation we ought to use, first we should evaluate what this sentence is. Break it down into its component parts. So we've already got these aforementioned fresnel lenses. Well, we know that this is a subject. So we've got fresnel lenses, that's our subject. What's the verb that they take? Are. Okay. So there's our verb are shaped. And then we're going to be looking for another noun that has a verb. Oh, there's another one. Rings. And then here's another verb, amplify and concentrate. So we've got a subject verb, punctuation, subject verb. And so what we're looking at here then is two independent clauses. So I'll bracket them off. So we're looking for one answer for a piece of punctuation that doesn't work. All the other answer choices should be able to unite independent clauses. So we're looking for the one outlier. The one thing that can't do that. So, okay. So option A. Semi-colon. What does a semi-colon do? It unites independent clauses. So right off the bat, we can say, alright, knock this one out. We know that this works so it is acceptable. We're looking for something that's not acceptable. Option B. Purpose, period, capital T, their. Well, so if we know that fresnel lenses are shaped in a specific way and for a very specific purpose, is a an independent clause. Remember that an independent clause can also just be a sentence. That is, in fact, why they are independent. So if this is a sentence, and this is also a sentence, then there's nothing wrong with dividing them up with a period and capitalizing the first letter of their. So, that checks out to me. Answer C. Well, now this is curious. We've got this comma here and we've got two independent clauses and we know that commas cannot unite independent clauses on their own. They need to be combined with a coordinating or a fanboys conjunction. That's the conjunction for, and, nor, but, or, yet, and so. And if you use a comma, plus a coordinating or fanboys conjunction, you can combine two independent clauses. But if you don't, if there's no fanboys, if it's just a comma on its own, that results in what we call a comma splice, which is ungrammatical. So right now, option C is looking like it might be our choice. Well, but let's see if we can eliminate answer choice D. Let's not jump to any conclusions. So this one uses a colon. Purpose, colon, their. Well, what are the powers of a colon? We know that the colon has the power to introduce things. How do you do? I'm the colon. The colon can introduce. Lists, rather like this one. Descriptions. Explanations or quotations. And also in order to use a colon, and a colon has to follow an independent clause. So what we're looking at here is an independent clause connecting to another independent clause. That's not a list, but it is kind of a description or explanation. Fresnel lenses are shaped in a specific way and for a very specific purpose, colon, their concentric rings amplify and concentrate light. So it describes their shapes, concentric rings. And it describes why, the purpose for amplifying and concentrating light. We're kind of using this punctuation mark the colon as an accelerating agent, right? We set up in this first independent clause that fresnel lenses have these particular properties and then we use the colon to build the momentum into the second independent clause. And so what does this mean? It means that we can use colons, which means we can knock out this answer, which means that C is our correct choice. When you're given a punctuation question, like this one, the first thing to do is to figure out the context of the sentence. You know, how many independent clauses or dependent clauses are you working with. Because that can change the landscape, and that can change the appropriate punctuation to use in that scenario.