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Plurals and possessives — worked example

Learn the best way to approach a plurals and possessives question on the SAT. To succeed on questions about plural and possessive nouns, you'll need to know the rules for using apostrophes with singular possessive nouns and plural possessive nouns. You'll also need to know the rules for possessive pronouns, and you'll need to be able to distinguish the possessive from a contraction (for example, "it's" versus "its"). Make sure to look for errors with possessives and plurals if the choices add or remove apostrophes or change the placement of apostrophes.. Created by David Rheinstrom.

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Video transcript

- [David] Hey, test takers, David here. We're looking at this question from the Reading and Writing test. If you'd like to try this one on your own before I work through it with you, go ahead and pause the video now. Okay, let's do this. Frequently misinterpreted by consumers, blank energy consumption, not their brightness. The brightness of a bulb is actually measured in lumens. Which choice completes the text so that it conforms to the conventions of Standard English? Okay, so when a question asks us about the conventions of Standard English, it's asking us about grammar, but which grammar convention is being tested here? Let's look at the choices. So these are all different versions of the same phrase with apostrophes in different places, and that tells us, and drum roll please, that this is a question about plurals and possessives. Ultimately, what these questions are about is where do you put the apostrophe? Knowing the rules around forming plurals and possessives in English is the key here. Only one of the choices will be free of errors and that's your answer. So let's review how to form plurals and possessives. A plural is just another way of saying more than one of a thing. One pineapple, two pineapples, right? You usually add an S to make a singular noun into a plural noun. There are exceptions, of course, like mouse and mice, goose and geese, sheep and sheep, but the SAT doesn't generally get into those, so we won't get into them much here. Possession, that's owning things. Grammatical possession for nouns requires an apostrophe and this is where it gets complicated. If we're talking about a singular noun, you just add an apostrophe and an S. The pineapple's smell, and that's true even if the singular noun ends in an S. The rhinoceros's horn. But if we're talking about a plural noun that ends in an S, you show possession by adding an apostrophe after the S. So the pineapples' smell, the rhinoceroses' horns. For plural nouns that don't end in an S, like children or mice, we use an apostrophe S, just like we would with a singular noun. The children's party, the mice's tails. Finally, there are possessive pronouns which never ever use apostrophes. This includes words like mine, yours, ours, his, hers, theirs, and its, no apostrophes. Whose pineapple is that? That pineapple is hers. I don't know why I'm so fixated on pineapples today. The point is this. These are the rules that you need to hold in your head when you take on one of these questions. Any choice that breaks any of these rules can be eliminated. Let's talk strategy real quick. First, restate the passage in your own words to understand its meaning. This will help you figure out how all of the nouns in the sentence should logically relate to each other. How many things are we talking about, and does any noun belong to another? Once you've got those relationships figured out, you can make a prediction about what form the nouns are going to take. Will they be possessive, or plural, or neither? Any choice that doesn't do exactly what you want will contain some kind of grammar error and can therefore be eliminated. The key here is, like I said, to understand the apostrophe rules so you can quickly identify those errors. So with that in mind, let's head back to our question. Let me refresh our memory on this question and then restate it. Frequently misinterpreted by consumers, watts measure lightbulbs' energy consumption, not their brightness. The brightness of a bulb is actually measured in lumens. So what's being misinterpreted by consumers? Watts are. What do they do? They measure the energy consumption of lightbulbs and not their brightness. So the plural verb conjugation measure tells us we want plural watts, right? Multiple watts measure. One watt measures. What comes after the blank belongs to the lightbulbs, their brightness, their energy consumption. So lightbulbs should be both plural and possessive. It owns both brightness and energy consumption. So we're looking for plural watts, no apostrophe, and plural possessive lightbulbs, so an apostrophe after the S. That's my prediction. Let's go through them. Choice A, possessive-singular watt, possessive-singular lightbulb, no good. Choice B, plural watts, yes. Plural possessive lightbulbs, boom, that's it. That's the one. Normally, on test A, I'd say we're done, move on. But let's keep going just to see. Choice C. Plural watts, good so far. Singular possessive lightbulb. Now, we're not talking about one lightbulb in this first sentence. We're talking about multiple lightbulbs, so no good. Choice D, singular possessive watt, that's a no. Plural possessive lightbulb. So it doesn't give us both things that we need. It's no good, cross it off. Okay, time for some top tips. Top tip number one. You need to check all the nouns in the underlined portion. This question had two nouns that we needed to check on. Both of them needed to be either apostrophe or not apostrophe correctly in the answer. Some answer choices might correctly form one noun but not the other. The other top tip is beware of its and their. These possessive pronouns are very easily confused with the contractions it's and they're, which is to say it is and they are. I say again, possessive pronouns don't use apostrophes. Good luck out there, test takers. You've got this.