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The damage caused by the series of storms was relatively minimal, but among the casualties were a cluster of farmhouses on the western outskirts of the town.
In this example, we are being tested on the subject-verb agreement. In order to effectively eliminate wrong answers and arrive at the correct answer, we’ll need to determine the subject by addressing who or what “was/where/are/have been among the casualties. This case is particularly tricky, as it involves subject-verb inversion - where the subject comes after the verb. The subject of the sentence that is referred to as “among the casualties” is “a cluster.” We describe the cluster as “a cluster of farmhouses” to provide additional context, but the subject “a cluster” itself is singular, despite being accompanied by a plural noun in its modifying context. With this in mind, the only answer option that agrees with the singular subject “a cluster” is “was.” “Were,” “are,” and “have been” are all plural verbs that would require a plural subject.
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There are two different ways to consider the so-called “Dark Ages.” On the one hand, you can think of the period directly after the fall of the Roman Empire, when civilization began to collapse throughout the Western Empire. On the other hand, you can consider the period that followed this initial collapse of society. It is a gross simplification to use the adjective dark to describe the civilization of either of these periods.
As regards the first period, it is quite a simplification to consider this period to be a single historical moment. It is not as though the civilization switched off like a lightbulb. At one moment light and then, at the next, dark. Instead, the decline of civilization occurred over a period of numerous decades and was, in fact, already occurring for many years before the so-called period of darkness. Thus, the decline of civilization was not a rapid collapse into barbarism, but instead, was a slow alteration of the cultural milieu of a partition of Europe. Indeed, the Eastern Roman Empire retained much of its cultural status during these years of decline!
More importantly, the period following the slow collapse of the Western Empire was much less “dark” than almost every popular telling state. Indeed, even during the period of decline, the seeds for cultural restoration was being sown. A key element of this cultural revival was the formation of monastic communities throughout the countryside of what we now know as Europe. Although these were not the only positive force during these centuries, the monasteries had played an important role in preserving and advancing the cause of culture through at least the thirteenth century and arguably until the Renaissance.
How should the underlined section be corrected?
The issue with the sentence as written is the fact that its main verb does not match the number of the sentence's subject. The subject is "seeds." Think of a simple sentence to check the verb: "The seeds were . . ." If you were to say, "The seeds was," you would immediately be aware of the error! The intervening expression "for cultural restoration" can distract you if you are not careful. Now, no additional commas are necessary. The "for" is a preposition, not a conjunction.
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To be considered true niche constructors, however, earthworms must change the environment in such a way as to alter the evolution of another species. One of the easiest ways to measure this effect on evolution has been in the effect that the number of earthworms 1 have on soil fertility, a measure of how hospitable an environment is to plant growth. Even the least fertile soil has around 62 worms per square meter, and as the number of worms increases so does soil fertility. As worms move through the different layers of soil, they eat, digest, and excrete massive amounts of organic matter. They leave their excretions behind in the form of nutrient-rich droppings known as casings. As these casings decompose, they release nutrients into the soil. This process not only moves nutrients from one layer of the soil to another but also converts the nutrients to forms that plants can absorb and process more easily.
The error in the original sentence is one of subject-verb agreement. The subject is “the number,” with “of earthworms” serving as a prepositional modifier that tells us more about the number. So the correct phrasing should be “the effect that the number (of earthworms) has on soil fertility…” Note that this occurs often on the ACT, with the authors of these questions adding descriptions (often in the form of prepositional modifiers) that include nouns, making your job of determining which subject goes with the verb a difficult one.
"Has on" is therefore correct. Among the other answer choices, "it has on" is incorrect because of the pronoun “it” between the subject, number of earthworms, and verb, has. And "can be to" uses improper diction: something can have an effect on something else, but to say that “its effect can be to” is an improper sentence structure.
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The traditional view of archaeologists usually involves a college professor who spends much of his or her time digging and researching in ancient foreign libraries or a museum curator who works every day to preserve the artifacts the museum holds. While this view isn’t completely incorrect, it is incomplete, both in terms of the types of jobs available to archaeologists and in the types of work within those jobs. For example, college professors may spend summers at dig sites, but much of their time is also spent writing grants, teaching students, and writing about their research projects. Additionally, although there are still many people who work in archaeology as professors and museum curators, the demand for these jobs far outstrips the number of positions available, making the positions difficult to acquire.
This problem asks you to find the proper form of the verb “work,” and showcases a handful of important lessons. For one, note that the verb “works” follows the relative pronoun “who” - this means that this verb applies specifically to the word that “who” is modifying, which is “curator.” So while this sentence involves many nouns, the only one that matters here is “curator.” For that reason, the noun must be singular, eliminating choices "work" and "do work", which are plural.
"Worked" is also incorrect, as the past tense implies that this curator in question has completed this work. Note that everything else in the sentence is ongoing: the traditional view “involves,” the professor “spends.” Therefore to suggest that this one action is completed while the others are ongoing is illogical, making this incorrect. The correct answer is "NO CHANGE", which uses a singular, ongoing verb “works.”
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Even today, lions can be seen ruling the African plains, hunting almost any animal that crosses its path and intimidating all but the most intrepid hunters.
In this example, we need to seek out relevant cues from outside the underlined portion of the sentence to identify what is needed out of the underline. Here, the singular vs. plural nature of the subject, lion vs. lions, is at question. If we continue to the latter portion of the sentence, we find the pronoun “its.” Since “its” refers back to the subject and is singular in nature, the subject, “the lion,” must also be singular. This leaves us with only “the lion rules,” our correct answer, as “lions can be seen ruling,” “lions are able to be seen ruling,” and “lions rule” all utilize the plural subject, “lions.”
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The quality of the new products that ACME Corporation has developed over the past year and that has recently arrived on retailers’ shelves worry many investors.
In this example, we are being tested on the subject-verb agreement. In order to effectively eliminate wrong answers and arrive at the correct answer, we’ll need to determine the subject by addressing who or what takes on each of our verbs: “have/has” at the start of our answer choices and “worry/worries” at the end. Using both logic and sentence structure, we can identify that what “have recently arrived on retailers’ shelves” are the products. So, the plural verb “have” is appropriate here, and we can eliminate all options that use the singular “has.”
From here, we’ll want to look at the subject taking on the verb “worry/worries.” If we read past or eliminate the modifying phrase “of the new products that ACME Corporation has developed over the past year and that \[have\] recently arrived on retailers’ shelves,” the core of the sentence reads “the quality worry.” Since quality is singular, the verb we need is “worries,” and we can eliminate any answer option that uses the plural “worry.” This leaves us with our correct answer: “have recently arrived on retailers’ shelves worries.”
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Each of the members of the board have at least ten years of experience working in nonprofit organizations.
In this example, we are being tested on the subject-verb agreement. In order to effectively eliminate wrong answers and arrive at the correct answer, we’ll need to determine the subject by addressing who or what takes on the verb “have/has/have had/had.” If we break down the construction of the sentence, “of the members of the board” is a modifying phrase referring back to the singular noun, “each.” Since “each” is singular, we need a singular agreement with our verb. Only “has” provides us with the singular agreement, as all other options either use the plural “have” or seem to imply that each member had experience, but does not anymore an illogical construction.
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The long-term effects of a high-sugar diet poses several consequences that should be considered when planning one’s trip to the grocery store.
In this example, we are being tested on subject-verb agreement. In order to effectively eliminate wrong answers and arrive at the correct answer, we’ll need to determine the subject by addressing who or what takes on the verb “pose/poses/has posed/has the potential to pose.” In this case, “of a high-sugar diet” is a modifying phrase. The core of the sentence reads “effects poses.” since “effects” are plural, we need the plural verb “pose.” Each of our incorrect answers incorrectly utilizes a singular verb in some form, which does not agree with the plural term “effects.”
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The number of applicants to top colleges and universities are increasing each year, even though there have been fewer high school graduates in each graduating class for the last seven years.
In this example, we are being tested on the subject-verb agreement. In order to effectively eliminate wrong answers and arrive at the correct answer, we’ll need to determine the subject by addressing who or what takes on the verb “are increasing,” or its alternative options. Here, “of applicants” and “to top colleges and universities” are both modifying phrases. The subject of the sentence taking on the verb is “the number.” Since “the number” is singular, we need a singular agreement, and only the option “is increasing” provides us with this singular agreement. We can also use logic for much of this question. Is the sentence trying to say that the universities are physically getting bigger? That the applicants are physically growing? Since both of these constructions are illogical, logic can point us to the correct and logical subject “the number.”
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Australia is known not only for its diverse landscapes, but also for their unique and often dangerous indigenous species.
In this example, we are being tested on noun-pronoun agreement and parallelism. In order to effectively eliminate wrong answers and arrive at the correct answer, we’ll need to determine the subject by addressing who or what we’re referring to with the pronoun “its/their.” In this case, we have a powerful hint in the non-underlined portion - we already refer to Australia using the pronoun “its.” So, we can see that the collective noun, Australia, is singular. We also need to maintain a parallel structure between what follows “not only” and what follows “but also.” Our correct answer, “but also for its” correctly refers to Australia using the singular possessive pronoun “its,” and introduces the phrase that follows the “but also” with the preposition “for” followed by the possessive pronoun and the object of possession - the same structure that follows the “not only” in the sentence.
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The Sagrada Familia has stood, incomplete, as part of the Barcelona skyline since the early phases of its construction in 1882. The project, originally intended to be a cathedral in the gothic style, was begun by the bookseller Joseph Maria Bocabella under the direction of the architect Francisco de Paula del Villar. Del Villar and Bocabella imagined a basilica modeled on the Gothic revival churches Bocabella had seen on trips to Italy. However, Bocabella’s ideal basilica never came to be. In 1883 del Villar resigned from the project, and 30-year old Antoni Gaudi, a young but already well-known architect from Catalonia, took over as lead architect.
Gaudi 1 decided that departing from del Villar’s original Gothic design in favor of a more modern design. The new design was ambitious, featuring eighteen tall spires and four different facades on different sides of the basilica. But work on the new building was slow. Decades passed, and the work was still incomplete. In 1915, Gaudi - now 63 years old - abandoned all other work in favor of dedicating himself to the completion of the monumental church, but progress on the building was still slow. When pressured to speed up work on the monumental building, Gaudi was said to have replied, “My client is not in a hurry.” By the time Gaudi died in 1926, the basilica was only somewhere between 15 and 20 percent complete.
Whenever you are choosing between different forms of the main verb of a sentence, you should check to make sure that the resulting sentence is in the appropriate tense and that it leaves a complete sentence. In this case, the given sentence is incomplete: if you are "deciding that departing" from a course of action, you are left without a main verb in the sentence and don't have a complete sentence. This means that choice, NO CHANGE, can be eliminated. The same logic can be used to eliminate "deciding in favor of departing" and "deciding to depart" since both will leave you with an incomplete sentence. The only choice, "decided to depart" leaves you with a complete sentence in the appropriate tense.
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Since 1988, the mission of molecular gastronomy 1 shifted. Kurti and This originally sought to investigate “kitchen old wives’ tales,” invent new recipes, improve old ones, and make the case to the public that science was a useful part of everyday life. Even if their experiments weren’t intended to be replicated in home kitchens, they were intended to encourage home cooks to experiment. Today, molecular gastronomists seek to explore the social, artistic, and technical aspects of food preparation. Some have argued that this shift in focus, along with the fact that techniques in molecular gastronomy have so far surpassed what any home cook could do, means that molecular gastronomy has lost its ability to impact how the world cooks at home.
Whenever you are asked to choose between different verb tenses, especially different forms of the past tense, you should look for signal words elsewhere in the passage that tells you which past tense form to use. In this case, you are given the word "since" at the beginning of the sentence, meaning that this process has been ongoing since 1988. Choices "shifted", "had shifted", and "has been shifted" all indicate that the shift has happened in the past and has ended. Only "has shifted" indicates that the change is still ongoing.
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Without earthworms, modern land-based ecosystems would look very different. There 1 are no way to predict the exact changes that would exist without earthworms, but it is easy to recognize earthworms’ impact. As research continues into the effect of earthworms, scientists are confident that it will show an even more complex picture of the earthworm’s contribution to the land-based ecosystem.
Whenever you have an inverted sentence like this one, remember that the subject comes directly after the verb (as long as what follows isn't a prepositional phrase!). In this case, that means that the subject of the sentence is "no way", a singular subject. That means that the answer must be either "was", "is", or "has been". To distinguish between them, look at the tense in the rest of the sentence. You must use "is" to keep the sentence in the present tense to match the rest of the sentence.
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Invertebrates are animals without vertebrae. Arthropods, including arachnids that has eight legs, are in this phylum. Some species in this phylum include scorpions, spiders, and ticks. There are over 45,000 known species of spiders; however, scientists estimate that the same number are still undiscovered.
With plural nouns, you need to make sure your verb agrees with your subject. In this modifier, "arachnids" is the subject, meaning the verb tense of "to have" needs to be conjugated to agree with the plural subject of "arachnids." "Have" is the only appropriate answer to this question because it not only agrees with the plural subject; it also carries the correct tense, which in this sentence is the present tense. "Have had" and "Had" are both in the past tense and do not work with this passage's tense and meaning. "Has" is incorrect because it does not agree with the plural "arachnids."
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Florida was first discovered by Europeans in 1513 by Juan Ponce de Leon. Its first city, St. Augustine, found shortly after in 1565. St. Augustine is known to be the oldest continuously inhabited European establishment. Prior to the colonization of Florida, many indigenous tribes resided there, such as the Apalachee, Seminoles, Timucua, and Creek.
Whenever the verbs in the passage are in the past tense, any verbs that follow need to keep with the same verb tense to create a meaning that is logical. This passage is written in the past tense, so the verbs need to agree with the past tense. “Founded” is the correct answer because this means “to found,” or establish something, such as a company or in this case: a city. “Find” and “Finds” are both in the present tense and would not agree with the sentence. “Found” is incorrect because, while still in the past tense, it expresses a different, illogical meaning.
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Music has been around for all of human history, and many cultures have their own styles and instruments. Recently, researchers have identified what are believed to be the oldest musical instruments in the world. Scientists has used carbon dating to discover that flutes made from bird bone and mammoth ivory found in southern Germany were between 42,000 and 43,000 years old.
In this passage, the verb does not need to be conjugated to the present perfect tense, which is done by adding “have” or “has,” since the verb is not ongoing “Used” is the correct option because it is the preterite of “use” which expresses a past action or state. “Have use,” “has use,” and “has used” are all conjugated incorrectly for the plural noun “scientists” and do not agree with the plural noun. “Used” is the only option that both correctly agrees with the plural noun and expresses a timeline that is logical.
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Most African cuisine traditionally uses a variety of local grains, fruits, and vegetables, as well as milk and meat products. Each region of Africa has different styles and traditional meals. In Central Africa, agriculture consists of yellow onions, yam, spinach, millet, bananas, okra, rice, and garlic. Many meat dishes there consist of chicken or goat. East African dishes focused primarily on grains, such as rice, flour for bread, millet, and maize, and have a plethora of stews cooked with meat and vegetables.
Whenever the passage is written in the present tense, the verbs used in the passage need to agree with the tense. “Focused” is not the correct answer because it is the simple past tense, and implies that these trends are no longer the case. “Will have focused” is in the future perfect tense, not the present. “Have focus” is an incorrect conjugation and would need to be written as “have focused” to be correct. “Focus” is the only option that is in the present tense and agrees with the subject. We can also use the verb “have” that appears later in the sentence at hand to better identify the correct timeline of events.
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There are many fish that live thousands of meters below the surface of the sea. These deep-sea creatures have adapted to their environment of little to no light. One creature, the vampire squid, is a small creature that grows to be around 6 inches in length and is the only surviving member of its order, Vampyromorphida. The vampire squid have long fins at the top of its body that serves as its means of propulsion, flying through the water by flapping these fins. The vampire squid’s body is covered with light-producing organs called photophores, allowing the vampire squid to use the chemical process known as bioluminescence to see in the dark depths of the ocean.
Whenever the passage is written in the present tense, the verbs used in the passage need to create a timeline of events that is logical. “Has had” is in the present perfect tense, but does not agree with the tense in the rest of the passage or the singular subject. You can identify the subject as singular and not plural due to the possessive pronoun “its” following the underlined portion of the sentence. If the subject were plural, the possessive would be “their” instead. “Had” is in the past tense and would not work. “Have” does not agree with the singular subject of the vampire squid, leaving “has” as the only correct option.
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The earliest known algebraic mathematical text was found in Egypt, dated to around 1650 BCE. This text shows that the ancient Egyptians could solve both linear equations and systems of equations. The ancient Greeks was best known for their discoveries in Geometry, including the Pythagorean Theorem.
The subject of the sentence is “Greeks,” which is a plural noun. The verb would need to agree with the plural subject, therefore “is,” “was,” and “has been” are incorrect because they are all singular verbs. The passage is also written in the past tense and would need to agree with tense and create a meaning that is logical, so “were” is the only choice that agrees with both the tense and the subject.
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Famous psychologist, Ivan Pavlov, is best known for his study of classical conditioning. Pavlov theorized that one learns through a pairing of a stimulus with a conditioned response. The experiment he conducted demonstrated how the presence of dog food would trigger a conditioned response. The dog food acted as the stimulus, while the conditioned response was that the dogs would salivate. In order to condition the response, every time Pavlov would feed the dogs, he would ring a bell. After he repeated this procedure, he would ring the bell without giving the dogs any food, which still triggered the conditioned response of salivation without the stimulus of food, proving his theory correct.
The passage is written in the past tense and “acted” is the only verb that agrees with that tense. The response “will act” does not work because it is in the future tense. The responses “acts” and “act” are both in the present tense and would also be incorrect. The subject, “food,” is singular, and “act” does not agree with the singular subject.
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