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Writing: Shift in verb tense and mood — Harder example

Writing: Grammar

Video transcript

- [Instructor] Ever since Alice discovered the secret elevator, she uses it to travel between the first and second floors and to avoid crowds in the hallway. Okay, so let's figure out what kind question this is. So we've got uses underlined, and that's our first answer choice, which is no change, has used, used, will have used. So the verb is the same, but its conjugations are changing. So this is a shift in tenses question. And something that I think is a very common mistake to make on a question like this is to concern yourself with matching tense across the sentence. So there's a real temptation to say well okay, we've got discovered here, so the only answer can be used, right, because this is simple past tense and this is simple past tense. But that may not necessarily be the case. There are all sorts of conditions in English that might trigger a shift from one verb tense to another. For example, when I go to the county fair, I will buy a deep fried stick of butter, say, for example. And so when I go, right, that's simple present tense, but then later in the sentence I say, I will buy, and that's simple future. And if you come at a sentence like that with the idea that all sentences need to maintain internal tense consistency, you're gonna say that's an incorrect sentence. But that's just not how language works. It needs to be dynamic, and you need to have the flexibility to shift between multiple tenses within a single sentence to represent the subject of the sentence's relationship to time. So with that idea hanging over all of this, let's go through this quite challenging question. So, ever since Alice discovered the secret elevator, she uses it, simple present, she uses it. This is something that happens habitually. This makes a lotta sense, but the presence of this like subordinating conjunctive phrase, ever since, has a conventional expression associated with it. This conventional expression triggers the use of the perfect tense. Otherwise it creates a kind of logical inconsistency. It's a conventional expression that both requires the perfect tense and has this connotation of continuous action. But what is the perfect tense? Normally we use the perfect tense to discuss actions that have completed. And we form the perfect tense by taking the verb to have and combining it with a past participle. Roberto had never flown before. Had flown is an example of the past perfect. We're saying that prior to this exact moment, Roberto had not flown. The flying had not taken place for him. Or we could say I have never been to Japan. Right, until this present moment, I have not yet gone to Japan. The Japan going has not yet happened. That's the present perfect. So even though this dependent clause takes place in the past, ever since brings us into the present, and it also signals that we need to use the perfect tense as well as having that continuous connotation. So let's cross out answer A. And this is why answer B is a good choice because it's still in the present tense, right. So ever since Alice discovered, and now here's something that is happening in the present as a result of that discovery. We can say has used. Another option would also be has been using. Ever since Alice discovered the secret elevator, she has been using it to travel between the first and second floors and to avoid crowds in the hallway. The key here is has. This is the present perfect. And the second option here is the present perfect continuous or the present perfect progressive. You see because ever since implies something that's ongoing. Has used would normally not have that implication, but because of ever since, it does take on that extra connotation. Used makes it seem like answer C, used, makes it seems like this happened once. Ever since Alice discovered the secret elevator, she used it to travel between the first and second floors and to avoid crowds in the hallway. Well that sounds like that just happened the one time, and we're really looking for something that is an ongoing event in the present. But we also know that if we just make this the present tense, it's gonna be answer A, which is incorrect because it doesn't have has, that thing that makes it the perfect tense. So this is no good either. And answer D, will have used, this is the future perfect tense. So if this is now, and this is the future, future perfect is a tense that takes place after now but just before the future. For example, by next Thursday, we will have used all of the toothpaste. Right, it's this thing that will have happened. So something that is in the future relative to the present, but in the past relative to the future. This is some of the most complicated temporal relations that English has to convey. That is why this is a difficult question. But we've got this thing ever since, which takes us into the present, necessitates the use of perfect, and we've got discovered here, which locates the discovery in the past. It wouldn't be grammatical to shift to talking about the future. There's no hints given in the sentence that shift us into thinking about the future. Strict consistency between tenses is not always the goal with questions like this or in the English sentence writ large. So we're going from simple past with discovered to present perfect with has used. And that's okay. Understanding that that kind of consistency isn't the goal is a very important thing to understand with questions like these and in your writing generally. There may be contexts that demand, as ever since does, that may demand different responses.