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Current time:0:00Total duration:4:50

Writing: End-of-sentence punctuation — Harder example

Writing: Grammar

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.