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5556 questions

Question 961Question

During the excavation of the ancient Roman villa, archaeologists discovered a cache of intricate, silver coins, they immediately cataloged the artifact details and photographed each piece.

Which option best replaces the underlined portion of the sentence?

Show answer & explanation

Answer: intricate silver coins; they immediately cataloged

Answer

The correct option is the one that reads 'intricate silver coins; they immediately cataloged'.
The correct answer correctly recognizes that 'intricate' and 'silver' are cumulative adjectives and should not be separated by a comma. It also correctly uses a semicolon to separate the two independent clauses.

Step-by-Step Solution

1
Determine if the adjectives modifying the noun are coordinate or cumulative.
The adjectives 'intricate' (opinion) and 'silver' (material) are cumulative because they cannot be reordered ('silver intricate coins' is incorrect) and cannot be joined by 'and'. Therefore, no comma should separate them.
This establishes whether a comma is required between 'intricate' and 'silver'.
2
Analyze the clause structure surrounding the underlined portion.
The clause before the underline ('During the excavation of the ancient Roman villa, archaeologists discovered a cache of...') is independent, and the clause after ('they immediately cataloged the artifact details and photographed each piece') is also independent.
This determines the appropriate punctuation needed to join the two clauses.
3
Evaluate the punctuation choices to join two independent clauses.
A semicolon is appropriate to separate two independent clauses, whereas a comma alone creates a comma splice. A semicolon followed by the subordinating conjunction 'because' incorrectly turns the second clause into a dependent fragment.
This allows us to select the correct punctuation mark that avoids both comma splices and fragments.

Key Concept

Identifying cumulative adjectives and properly separating independent clauses with semicolons.
Question 962Question

Crows are remarkably intelligent birds capable of solving complex, multi-step puzzles. [1] Consequently, they have been observed using twigs to extract insects from deep crevices in tree bark, demonstrating advanced tool-use abilities.

Which choice provides the most logical transition from the preceding sentence?

Show answer & explanation

Answer: For instance,

Answer

The transition phrase 'For instance' is correct because it logically connects the general statement about crow intelligence in the first sentence to the specific example of tool use in the second sentence.
The correct answer is the phrase indicating an illustration. The first sentence makes a general assertion about the high intelligence and problem-solving abilities of crows. The second sentence provides a specific, concrete example of this intelligence by describing their use of twigs to extract insects. The phrase 'For instance' correctly signals this illustrative relationship.

Step-by-Step Solution

1
Analyze the relationship between the first sentence (which states that crows are highly intelligent and solve complex puzzles) and the second sentence (which describes crows using twigs to extract insects).
Identify that the second sentence serves as a specific, concrete example of the general statement in the first sentence.
To choose the correct transition, we must understand the logical connection between the two ideas.
2
Evaluate the transition options to find the one that denotes an illustrative or exemplifying relationship.
Determine that 'For instance' is an illustration transition, while 'Consequently' is cause-and-effect, 'However' is contrast, and 'Similarly' is comparison.
Matching the logical relationship to the correct category of transition words ensures clarity and cohesion.

Key Concept

Sentence-Level Transitions
Question 963Question

The following is an excerpt from an essay about geological discoveries.

[1]
__________________________________________________ Prior to Danish seismologist Inge Lehmann's groundbreaking publication in 1936, scientists believed that the Earth's core was a single, uniform liquid sphere. By analyzing seismic waves from a major earthquake in New Zealand, Lehmann observed that some P-waves were unexpectedly deflected, or diffracted, deep within the Earth. She reasoned that this deflection could only be caused by a distinct, solid inner core nested inside the liquid outer core. Her hypothesis was eventually confirmed by more advanced instruments, redefining the field of seismology.

Which choice provides the most effective introduction to the paragraph?

Show answer & explanation

Answer: In 1936, Danish seismologist Inge Lehmann published a paper that fundamentally altered our understanding of Earth's interior.

Answer

The correct option is the sentence introducing Inge Lehmann's 1936 publication, as it is grammatically correct and directly establishes the topic of the passage.
The correct option successfully introduces the main topic of the paragraph, which is Danish seismologist Inge Lehmann's discovery of the Earth's solid inner core. It is grammatically correct and flows logically into the subsequent sentence that describes beliefs prior to Lehmann's publication.

Step-by-Step Solution

1
Analyze the main focus of the paragraph.
The paragraph discusses the discovery of the Earth's solid inner core by Inge Lehmann in 1936, contrasting her findings with prior beliefs about a uniform liquid core.
Understanding the central theme is necessary to identify which sentence best introduces the topic.
2
Evaluate the options for grammatical correctness and relevance.
The correct choice must be a complete, grammatically correct sentence that introduces Lehmann or the core structure discovery. The other options contain grammar errors (subject-verb agreement, fragments, or incorrect semicolon usage) and focus on off-topic details like wave types, core composition, or general seismology.
Eliminating grammatically flawed and off-topic sentences leaves the option that serves as a proper topic sentence.
3
Select the option that establishes a clear transition into the next sentence.
The statement introducing Lehmann's 1936 publication perfectly sets up the contrast in the next sentence: 'Prior to Danish seismologist Inge Lehmann's groundbreaking publication in 1936, scientists believed...'
An effective introduction must connect logically to the sentences that follow it.

Key Concept

Establishing an effective introduction that matches the focus of the paragraph while maintaining grammatical correctness.
Question 964Question

Passage

In 1965, chemist Stephanie Kwolek was analyzing synthetic fiber chains at DuPont in search of a lightweight material to reinforce car tires. During her experiments, she generated a strange, cloudy solution that looked unlike the thick, clear polymers she typically worked with. Rather than discarding the unusual mixture, Kwolek convinced a colleague to run it through a spinneret, a machine used to draw liquid polymers into fibers. The resulting fiber was astonishingly strong—five times stronger than steel on a pound-for-pound basis—and resistant to both heat and corrosion. [1]

DuPont quickly recognized the commercial potential of this new material, trademarking it as Kevlar. In the decades following Kwolek's discovery, Kevlar found applications in racing sails, bicycle tires, and optical fiber cables. Most notably, its high tensile strength and lightweight nature revolutionized personal armor, saving the lives of countless military personnel and law enforcement officers.

Question

The writer wants to add a sentence at the end of the first paragraph (at point [1]) to conclude the discussion of Kwolek’s laboratory discovery and transition to the next paragraph's focus on Kevlar's commercial applications. Which of the following sentences best accomplishes this goal?

Show answer & explanation

Answer: This breakthrough laboratory experiment laid the foundation for a material that would soon find widespread utility in various industries.

Answer

The sentence that describes the laboratory experiment laying the foundation for a material that would find widespread utility in various industries is the correct choice.
The correct option effectively concludes the first paragraph's focus on Stephanie Kwolek's laboratory discovery while transitioning to the second paragraph's focus on Kevlar's commercial applications. By stating that the experiment laid the foundation for widespread utility in various industries, it connects the scientific breakthrough with its subsequent practical uses.

Step-by-Step Solution

1
Analyze the purpose of the sentence to be inserted.
The sentence must conclude the first paragraph (laboratory discovery) and transition to the second paragraph (commercial applications).
An effective conclusion-transition sentence must bridge the two paragraphs' main ideas logically.
2
Evaluate the options for structural cohesion and relevance.
The correct choice must connect the laboratory breakthrough to industrial applications without introducing unrelated facts.
Sentences introducing Kwolek's childhood or award history distract from the passage's flow.
3
Check for grammatical correctness in the remaining options.
The option with a comma splice is grammatically incorrect, and the option with present-tense verbs shifts tenses inappropriately.
ACT English questions require sentences to be both rhetorically effective and grammatically correct.

Key Concept

Selecting Concluding Sentences and Transitions
Question 965Question

The following paragraphs are from an essay about linguistic relativity and spatial orientation.

Paragraph 1
Many cognitive scientists once believed that human spatial orientation was universally egocentric, relying on self-centered coordinates such as 'left,' 'right,' 'front,' and 'back.' However, research on the Guugu Yimithirr language of northeastern Australia challenged this assumption. Guugu Yimithirr speakers do not use relative spatial terms; instead, they rely entirely on absolute cardinal directions—north, south, east, and west—to describe the position of everything, from geographic landmarks to minor household objects. This requires them to maintain a constant, subconscious awareness of their geographic orientation, effectively keeping a running compass in their minds at all times.

Paragraph 2
[1] This cognitive difference manifested in how speakers of different languages describe everyday, local spaces. For example, if an English speaker wants another person to move a cup on a table, they might say, 'Move it a bit to your left.' In contrast, a Guugu Yimithirr speaker would say the equivalent of, 'Move it a bit to the north-northwest.' If the listener turned around, the English speaker's instructions would have to change to remain accurate, but the Guugu Yimithirr speaker's directions would remain exactly the same.

Which choice provides the most effective transition from the preceding paragraph?

Show answer & explanation

Answer: This cognitive difference manifests in how speakers of different languages describe everyday, local spaces.

Answer

The option that states 'This cognitive difference manifests in how speakers of different languages describe everyday, local spaces.'
The correct option uses the appropriate present-tense verb 'manifests' and the idiomatic preposition 'in.' Rhetorically, it provides a cohesive bridge by taking the abstract cognitive difference established in the first paragraph and showing how it applies to the concrete, everyday spatial descriptions that follow in the second paragraph.

Step-by-Step Solution

1
Analyze the preceding paragraph
The first paragraph explains how Guugu Yimithirr speakers use absolute cardinal directions, establishing a constant cognitive awareness of geographic orientation (a 'running compass').
Understanding the starting point of the transition is necessary to build a logical bridge.
2
Analyze the following paragraph
The second paragraph provides a concrete example comparing how English speakers and Guugu Yimithirr speakers describe local space (such as moving a cup on a table).
Understanding the destination of the transition is necessary to ensure the bridge connects to the right idea.
3
Identify the transitional requirements
The correct option must connect the concept of 'cognitive difference' from the first paragraph to the concept of 'describing everyday, local spaces' from the second paragraph.
This establishes coherence and unity between the two paragraphs.
4
Eliminate grammatically incorrect options
Eliminate the choice with the past-tense verb 'manifested' due to an illogical tense shift, and eliminate the choice with the preposition 'at' due to an idiomatic error.
ACT English questions require both rhetorical effectiveness and grammatical correctness.
5
Evaluate remaining options for redundancy and relevance
Eliminate the choice about navigating the wilderness because it is redundant and does not lead into the example about local space, leaving the correct option.
Selecting the most concise and transitionally effective choice completes the rhetorical task.

Key Concept

Paragraph-Level Transitions
Estimated Time:1m 30s
Question 966Question

[1]
__________________________________________________

[2] While working with Charles Babbage on his plans for the Analytical Engine, a mechanical general-purpose computer, Lovelace translated an article by Italian military engineer Luigi Menabrea. [3] In her translation, which she expanded with an extensive set of notes, she described an algorithm for the Analytical Engine to compute Bernoulli numbers. [4] This algorithm is now widely recognized as the world's first computer program, demonstrating that Lovelace foresaw the machine's capability to process symbolic representations beyond mere numerical calculation.

The writer is considering adding a sentence at the beginning of the passage (before Sentence 2) to introduce the main thesis of the essay. Which of the following sentences would best accomplish this goal?

Show answer & explanation

Answer: In the mid-nineteenth century, mathematician Ada Lovelace laid the conceptual groundwork for computer programming, anticipating the modern digital age long before the technology existed.

Answer

The sentence starting with 'In the mid-nineteenth century' is the best introduction and thesis statement because it is grammatically correct and establishes the primary focus of the passage: Ada Lovelace's pioneering work in computer programming and her vision of symbolic processing.
The correct sentence starting with 'In the mid-nineteenth century' is grammatically correct and successfully introduces the main thesis of the passage. It establishes Ada Lovelace as a pioneer who laid the conceptual foundation for programming and anticipated the digital age, which sets up the discussion of her work on Charles Babbage's Analytical Engine and her creation of the first algorithm.

Step-by-Step Solution

1
Analyze the main focus and details of the passage.
The passage discusses Ada Lovelace's translation of Luigi Menabrea's article, her creation of an algorithm to compute Bernoulli numbers (the first computer program), and her foresight that the Analytical Engine could process symbols beyond numbers.
An effective introduction or thesis statement must establish the central theme of the passage, which is Lovelace's pioneering contribution to computer programming.
2
Evaluate the options for grammatical correctness and sentence structure.
The sentence beginning with 'Although Charles Babbage' is a dependent clause fragment. The sentence beginning with 'Ada Lovelace's extensive notes' has a subject-verb agreement error ('notes ... represents'). The sentence beginning with 'Ada Lovelace was a brilliant mathematician' is a comma splice.
Options with grammatical errors must be eliminated since ACT English requires standard grammatical correctness.
3
Assess the remaining option for thematic fit and overall quality.
The sentence starting with 'In the mid-nineteenth century' is grammatically correct and directly introduces Lovelace's foundational role in programming, which aligns perfectly with the details in the passage.
This sentence serves as an effective introduction and thesis statement for the passage.

Key Concept

Establishing an effective introduction or thesis statement requires selecting a grammatically correct sentence that introduces the main topic and prepares the reader for the details that follow in the passage.
Question 967Question

The following paragraphs are from an essay about the decipherment of Mayan hieroglyphs. Arrange the paragraphs in the most logical order to create a cohesive passage.

Drag items to arrange them in the correct order

Show answer & explanation

Answer

The paragraphs should be ordered as follows: first, the paragraph describing the initial scholarly consensus that Mayan glyphs were not phonetic; second, the paragraph introducing Yuri Knorozov's breakthrough that challenged this deadlock; and third, the paragraph detailing the subsequent decipherment and legacy of this research.
The correct order establishes a logical progression: it starts with the historical consensus that glyphs were not phonetic, transitions to Yuri Knorozov breaking this scholarly deadlock in the 1950s, and ends with how other researchers built on Knorozov's breakthrough to read classic Mayan inscriptions today.

Step-by-Step Solution

1
Analyze the opening sentences of each paragraph to identify transitional words or reference phrases.
One paragraph begins with 'Building on Knorozov's phonetic breakthrough', indicating it must follow a paragraph introducing Knorozov. Another paragraph begins with 'This scholarly deadlock', implying it must follow a paragraph describing a consensus or lack of progress.
Paragraph-level transitions rely on lexical and conceptual connections, such as pronouns, demonstrative adjectives, and chronological markers.
2
Identify the introductory paragraph that establishes the initial context.
The paragraph describing the long-held belief that Mayan glyphs were purely symbolic and could not be translated phonetically sets up the context of a rigid scholarly consensus.
This paragraph has no preceding references and introduces the topic, making it the logical start.
3
Match the transition phrases to connect the remaining paragraphs.
The paragraph starting with 'This scholarly deadlock' refers to the rigid consensus described in the first paragraph. The paragraph starting with 'Building on Knorozov's phonetic breakthrough' refers to the phonetic work established in the Knorozov paragraph.
Connecting these referring phrases ensures a logical flow from consensus, to breakthrough, to modern impact.

Key Concept

Identifying paragraph-level transition cues to arrange ideas in a logical sequence.
Estimated Time:1m 30s
Question 968Question

In the late nineteenth century, socialite Josephine Cochrane grew frustrated with the frequent chipping of her fine china during hand-washing. Resolving to design a mechanical solution, she measured her dishes, constructed wire compartments to hold them secure, and coupled these with a copper boiler and a hand-cranked water pump. Her invention was a success, washing dishes quickly and safely. Cochrane’s design was patented in 1886 and went on to win top honors at the 1893 World's Columbian Exposition.

At first, the commercial dishwasher found its primary market in hotels and restaurants, which valued the machine’s efficiency and sanitation capabilities. However, Cochrane continued to refine her design, envisioning a future where every home would have one. [1]

Which of the following sentences, if added at point [1], would provide the most logical transition and effective conclusion to the passage?

Show answer & explanation

Answer: Through her persistent innovations, she successfully transformed a specialized commercial tool into a ubiquitous household convenience.

Answer

The sentence that describes the transformation of a commercial tool into a ubiquitous household convenience.
The sentence describing the transformation of the dishwasher into a household convenience is correct because it links Cochrane's aspiration for domestic use with the ultimate commercial success of the appliance, wrapping up the paragraph's theme and the passage's narrative flow.

Step-by-Step Solution

1
Analyze the context and preceding sentence.
The final paragraph explains the transition of the dishwasher from commercial use (hotels and restaurants) to residential use, concluding with Cochrane's vision of home adoption.
An effective concluding sentence must connect back to these points and summarize the main achievement without introducing irrelevant facts or grammatical errors.
2
Evaluate the choices for relevance and grammatical correctness.
The statement about transforming a commercial tool into a household convenience logically completes the narrative arc. Other options either introduce unsupported details (another patent) or are grammatically flawed.
Eliminating options with irrelevant details and grammatical errors ensures the best stylistic and conceptual fit.

Key Concept

Selecting Concluding Sentences and Transitions
Question 969Question

The following is an excerpt from an essay about eighteenth-century zoology.

[1]
_____________________. When the first specimen arrived in England from Australia in 1799, British naturalists were convinced it was a clever hoax. George Shaw, the keeper of natural history at the British Museum, even used a pair of scissors to inspect the dried pelt, searching for the stitches he assumed were binding a duck’s bill to a beaver-like body. However, as more specimens arrived, scientists had to accept that this bizarre creature, with its webbed feet, fur, and venomous spurs, was indeed real.

Which choice most effectively introduces the paragraph and establishes the main topic of the passage?

Show answer & explanation

Answer: The duck-billed platypus has long baffled the scientific community with its unique blend of mammalian and avian characteristics.

Answer

The duck-billed platypus has long baffled the scientific community with its unique blend of mammalian and avian characteristics.
The correct option stating that the platypus baffled the scientific community with its mammalian and avian features is correct because it introduces the specific subject of the paragraph (the platypus) and directly connects to the subsequent sentences describing the naturalists' disbelief and the animal's bizarre physical traits.

Step-by-Step Solution

1
Identify the primary topic and focus of the paragraph.
The paragraph describes the arrival of the platypus specimen in England, the disbelief of the naturalists, and their eventual realization that the bizarre creature was real.
The correct introduction must establish the platypus as the central subject and set up the theme of scientific skepticism.
2
Evaluate the choices for relevance and focus.
The option focusing on the duck-billed platypus baffling the scientific community directly introduces the paragraph's subject and theme. Other options are either too general or grammatically flawed.
An effective introduction must align logically with the supporting details in the passage.
3
Check the remaining options for grammatical errors.
The option beginning with 'Naturalists in the eighteenth century' contains a comma splice. The option starting with 'The discovery of various' has a subject-verb agreement error. The option starting with 'Although early explorers' contains an inconsistent tense shift.
Eliminating grammatically incorrect distractors confirms the validity of the correct choice.

Key Concept

Establishing Introductions and Thesis Statements
Question 970Question

For centuries, travelers in deep forests have reported witnessing an eerie, soft green glow emanating from decaying wood. Known colloquially as "foxfire," this natural phenomenon is caused by bioluminescent fungi that produce light through a chemical reaction. While researchers have long understood the chemical basis of this glow, they struggled to explain its evolutionary purpose, questioning why a fungus would expend valuable energy to shine in the dark.

[1]

A team of researchers discovered that the green light attracts nocturnal insects, such as beetles, flies, and wasps. These insects crawl over the glowing mushrooms, inadvertently collecting spores on their bodies, and subsequently distribute them throughout the forest floor. By shining in the night, the fungi ensure the dispersal of their offspring.

Which choice provides the most effective transition from the preceding paragraph to the paragraph that follows?

Show answer & explanation

Answer: A recent study finally provided an answer to this mystery.

Answer

The correct choice is the phrase that states a recent study finally provided an answer to this mystery.
The preceding paragraph ends with a question about the evolutionary purpose of bioluminescent fungi. The following paragraph begins by describing a scientific discovery explaining how this glow helps disperse spores. The correct choice transitions smoothly by stating that a study provided an answer to this mystery, linking the question directly to the answer. It is grammatically correct, using the past-tense verb to match the narrative and the correct preposition 'to' after 'answer'.

Step-by-Step Solution

1
Analyze the relationship between the two paragraphs.
The first paragraph ends by introducing an evolutionary question (why fungi glow), and the second paragraph begins by presenting the research findings (the discovery of insect attraction for spore dispersal).
The correct transition must logically bridge this question-and-answer relationship.
2
Evaluate each option for rhetorical effectiveness and grammatical correctness.
The option stating that a study provided an answer to this mystery fits the context perfectly and is grammatically sound.
It maintains past-tense consistency and uses correct idiomatic preposition usage.

Key Concept

Paragraph-Level Transitions
Estimated Time:1m 0s
Question 971Question

[1]
In 1957, engineers Alfred Fielding and Marc Chavannes set out to create a three-dimensional textured wallpaper. By sealing two plastic shower curtains together, they trapped small pockets of air to create the desired texture. Unfortunately, this wallpaper design failed to attract buyers, leaving the inventors with a product but no market.

[2]
A few years later, in 1959, IBM announced the launch of its new 1401 computer, a delicate piece of electronic equipment that needed protective packaging during shipping. Fielding and Chavannes realized that their air-filled plastic sheets were perfect for protecting fragile items during transit. They pitched their product to IBM, which began using it to wrap their computers, launching the brand we now know as Bubble Wrap.

[3]
Today, Bubble Wrap is a staple of shipping departments and packing boxes worldwide, manufactured in multiple countries and generating millions in annual revenue. What started as a home decor failure became a packaging triumph, demonstrating how a change in perspective can transform a simple idea.

[4]
Hoping to salvage their invention, the pair began searching for alternative uses for their bubbly plastic sheets. They first marketed it as greenhouse insulation, but that idea also failed to gain traction.

To make the essay flow most logically, where should Paragraph 4 be placed?

Show answer & explanation

Answer: following Paragraph 1

Answer

following Paragraph 1
The correct answer is the option stating that Paragraph 4 should be placed following Paragraph 1. Paragraph 1 introduces the invention of textured wallpaper in 1957 and its subsequent failure. Paragraph 4 details the inventors' immediate next steps ('Hoping to salvage their invention') and another failed attempt. This logically sets up Paragraph 2, which begins with the transition 'A few years later, in 1959,' and describes their ultimate success with IBM.

Step-by-Step Solution

1
Analyze the chronological markers and narrative development of the essay.
The essay starts in 1957 with the creation and failure of wallpaper (Paragraph 1), jumps to success with IBM in 1959 (Paragraph 2), and ends with its modern success today (Paragraph 3).
To understand the chronological progression of the events described.
2
Identify the transition and referential clues in the paragraph to be placed.
Paragraph 4 starts with 'Hoping to salvage their invention,' indicating it must follow the failure mentioned in Paragraph 1. It describes an unsuccessful attempt (greenhouse insulation) that must occur before the successful IBM partnership in 1959.
To determine the logical relationships and dependencies between paragraphs.
3
Select the correct position that preserves the narrative and logical flow.
Placing Paragraph 4 immediately after Paragraph 1 creates a smooth, chronological flow from 1957 wallpaper failure -> salvage attempts -> 1959 success -> modern legacy.
To maintain coherent transitions and logical progression throughout the essay.

Key Concept

Paragraph Reordering and Placement
Estimated Time:1m 0s
Question 972Question

In the late nineteenth century, Thomas Edison's phonograph introduced the wax cylinder, the first commercial medium for recording and reproducing sound. These fragile cylinders captured invaluable early musical performances, spoken-word recordings, and oral histories. However, because wax degrades rapidly when exposed to humidity and physical playback wears down the grooves, playing these recordings carries a high risk of destroying them forever.

To solve this, researchers developed IRENE, a non-contact optical scanning system that creates ultra-high-resolution digital images of the cylinders' grooves. Software then reconstructs the audio from these digital maps, bypassing the need for physical contact. [1] This non-contact system, that utilizes digital photography, will preserve the fragile cylinders for future generations.

Which choice most effectively concludes the paragraph by emphasizing how the digital scanning technology solves the problem of preserving fragile historical recordings?

Show answer & explanation

Answer: By rescuing these voices from silence, this technology ensures that future generations can listen to the auditory heritage of the past.

Answer

By rescuing these voices from silence, this technology ensures that future generations can listen to the auditory heritage of the past.
The correct option successfully concludes the passage by highlighting the long-term benefit of the scanning technology (preserving and sharing auditory heritage) without introducing unrelated details or grammatical errors.

Step-by-Step Solution

1
Analyze the passage's main thesis and paragraph flow.
The passage discusses the fragility of historical wax cylinders and how a new non-contact scanning technology is used to reconstruct the audio without physical damage.
An effective concluding sentence must summarize or reinforce this main idea without introducing unrelated details.
2
Evaluate the options for logical relevance and tone.
The option about Edison's other inventions introduces irrelevant information. The option about rescuing voices from silence directly reinforces the goal of preserving historical recordings using the scanning technology.
Concluding sentences must not introduce unsupported details.
3
Examine the remaining options for grammatical correctness.
The original sentence contains a restrictive clause error (commas around 'that'). The option about researchers playing cylinders contains a comma splice. The option about rescuing voices from silence is grammatically correct.
The correct answer must be grammatically correct and stylistically appropriate.

Key Concept

Selecting Concluding Sentences and Transitions
Question 973Question

A writer is editing a draft of an essay about the discovery of the coelacanth.

In 1938, Marjorie Courtenay-Latimer, a South African museum curator, discovered an unusual fish among the catch of a local trawler. Recognizing its unique features—including lobed fins that resembled limbs—she contacted ichthyologist J.L.B. Smith to help identify it. Smith recognized the specimen as a coelacanth, a member of a lineage believed to have gone extinct 66 million years ago. [1] Prior to this discovery, scientists had only studied the prehistoric fish through fossilized remains. The find, often referred to as the 'living fossil' discovery, completely reshaped scientific understanding of vertebrate evolution.

At this point, the writer is considering adding the following true statement:

Fossils are formed when organic material is slowly replaced by minerals over millions of years.

Should the writer make this addition at point [1]?

Show answer & explanation

Answer: No, because it interrupts the focus of the paragraph by introducing a general definition of fossilization that is tangential to the discovery of the coelacanth.

Answer

No, because it interrupts the focus of the paragraph by introducing a general definition of fossilization that is tangential to the discovery of the coelacanth.
The correct option correctly identifies that the proposed sentence should not be added because it introduces a general definition of fossilization, which is tangential to the paragraph's focus on the narrative of the 1938 coelacanth discovery.

Step-by-Step Solution

1
Analyze the main focus of the paragraph.
The paragraph describes the narrative of Marjorie Courtenay-Latimer's 1938 discovery of a live coelacanth and the significance of this discovery for science.
Understanding the paragraph's primary topic is necessary to evaluate if the proposed sentence is relevant.
2
Evaluate the relevance of the proposed sentence.
The proposed sentence defines how fossils are formed over millions of years. This is a general geological concept that is not directly related to the story of the 1938 discovery.
This step determines whether the sentence adds meaningful information that aligns with the established topic.
3
Formulate the decision and choose the option with the correct reasoning.
The sentence should not be added because it is tangential and interrupts the narrative flow. The option stating that it interrupts the paragraph by introducing a general definition of fossilization is the correct choice.
This step matches the analysis to the correct decision and logical justification among the choices.

Key Concept

Evaluating Relevance for Adding or Deleting Content
Estimated Time:1m 0s
Question 974Question

The following paragraphs are from an essay about a major marine science breakthrough. For the sake of the logic and cohesion of this essay, arrange the paragraphs in the most logical order.

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Answer

The correct sequence of paragraphs is: the paragraph introducing the historical view of the ocean floor as a desert; followed by the paragraph describing how this view was challenged by the 1977 expedition; followed by the paragraph describing the explorers' surprise discovery of dense marine life; followed by the paragraph explaining that these creatures survived via chemosynthesis; and concluding with the paragraph detailing the landmark legacy of the discovery.
The correct order follows a clear logical progression: first introducing the initial scientific assumption, then introducing the event that challenged it, then describing the findings of the event, followed by explaining the mechanism of these findings, and finally detailing the legacy of the entire discovery.

Step-by-Step Solution

1
Identify the introductory paragraph that establishes the main topic and context without relying on preceding context.
The paragraph starting with 'For decades, oceanographers operated under the assumption...' is the only one that does not contain transition words, backward-looking pronouns, or references to prior events. It establishes the baseline assumption that the deep ocean floor is devoid of life.
An essay must begin with a clear introduction that provides necessary context for subsequent details.
2
Look for a paragraph that directly connects to the introductory assumption.
The paragraph starting with 'This prevailing view was dramatically challenged in 1977...' contains the demonstrative phrase 'This prevailing view,' which refers directly to the assumption that the ocean floor is a biological desert. This paragraph also introduces the 1977 expedition.
Demonstrative pronouns and adjectives must immediately follow their antecedents to maintain cohesion.
3
Trace the narrative of the expedition introduced in the previous step.
The paragraph starting with 'Expecting to find only volcanic rocks...' refers to the scientists from the previous paragraph as 'the explorers' and describes what they found upon descending into the Galapagos Rift.
Chronological and narrative flow dictates that the arrival and immediate observations of the expedition must follow its introduction.
4
Find the paragraph that explains the details of the creatures discovered.
The paragraph starting with 'Rather than relying on solar energy, these unique creatures...' refers back to the giant tubeworms and blind crabs from the previous paragraph using the phrase 'these unique creatures.' It explains the chemical process (chemosynthesis) behind their survival.
Noun phrases like 'these unique creatures' require a clear, preceding referent to make logical sense.
5
Identify the concluding paragraph that summarizes the significance of the event.
The paragraph starting with 'This landmark discovery...' refers to the entire sequence of events and findings as 'this landmark discovery' and explains its long-term impact on marine biology and space exploration.
Concluding paragraphs typically synthesize the information presented and discuss its broader implications, often starting with summarizing references.

Key Concept

Using transition words, pronoun antecedents, and logical narrative progression to determine the correct order of paragraphs in a passage.
Estimated Time:2m 0s
Question 975Question

The following paragraphs are from an essay about the construction of the Eddystone Lighthouse and the development of modern cement. To make the essay most logical and cohesive, in what order should the paragraphs be arranged?

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Answer

The paragraphs must be arranged in the sequence starting with the historical failures of wooden structures on the reef, followed by John Smeaton's transition to stone and the mortar issue, then the chemical experiments resulting in hydraulic lime, and ending with the completion of the lighthouse and the global legacy of modern cement.
The correct sequence flows from the historical background of the reef's hazards and early wooden failures, to John Smeaton's decision to use stone and his discovery of the mortar problem, to his subsequent experimental research creating hydraulic lime, and finally to the physical construction of the tower and its long-term impact on modern civil engineering.

Step-by-Step Solution

1
Identify the introductory paragraph.
The paragraph introducing the location (Eddystone Rocks) and the initial structural failures (wooden lighthouses being swept away) sets the historical context and must come first.
An essay must establish the setting and the primary problem before detailing individual efforts to solve it.
2
Find the bridge from timber failures to Smeaton's project.
The paragraph noting that John Smeaton sought a material 'far sturdier than wood: stone' directly picks up the thread of timber's inadequacy and introduces the chemical challenge of underwater mortar.
This paragraph explicitly references the wooden materials from the first paragraph and sets up the primary chemical conflict of the essay.
3
Locate the resolution to the mortar setting problem.
The paragraph beginning with 'To overcome this barrier' describes Smeaton's chemical experiments and his ultimate development of hydraulic lime.
The phrase 'this barrier' links directly back to the previous paragraph's concluding point about traditional lime mortar washing away before setting in water.
4
Identify the concluding paragraph and its transition.
The paragraph beginning 'Armed with this revolutionary binding agent' completes the narrative by describing the building's construction and its broader legacy.
The phrase 'this revolutionary binding agent' refers to the 'hydraulic lime' developed in the preceding paragraph, and the text shifts from the specific build to a broad, global historical summary.

Key Concept

Paragraph-Level Transitions
Estimated Time:2m 30s
Question 976Question

Created in the early 1830s, *The Great Wave off Kanagawa* is one of the most recognizable works of Japanese art. The woodblock print, which depicts three boats navigating a towering wave, features the iconic Prussian blue pigment. This masterpiece helped secure Hokusai's legacy as a pioneer in landscape composition.

Which of the following options correctly punctuates the underlined portion of the sentence?

Show answer & explanation

Answer: NO CHANGE

Answer

NO CHANGE
The correct option properly uses a pair of commas to set off the nonessential relative clause, keeping the sentence grammatically complete and clear.

Step-by-Step Solution

1
Determine if the underlined clause provides essential or nonessential information.
The clause 'which depicts three boats navigating a towering wave' provides additional descriptive information about the woodblock print but is not essential for identifying it. Thus, it is nonessential.
Nonessential information must be set off by punctuation, whereas essential information should not be separated.
2
Apply the correct punctuation to enclose the nonessential element.
Since the nonessential clause is positioned in the middle of the sentence, it must be enclosed by a pair of commas: one after 'print' and one after 'wave'.
A pair of commas prevents the sentence from feeling interrupted or grammatically incorrect.

Key Concept

Commas with Nonessential and Parenthetical Elements
Question 977Question

The following paragraphs are from an essay about the decipherment of the ancient Maya hieroglyphic script. Arrange the paragraphs in the most logical order to create a cohesive passage.

Drag items to arrange them in the correct order

Show answer & explanation

Answer

The paragraphs should be ordered as follows: first, the paragraph establishing the historical mystery and early consensus; second, the paragraph introducing Knorozov's phonetic methodology; third, the paragraph detailing his testing of the hypothesis using Diego de Landa's manuscript; and finally, the paragraph describing the ultimate triumph and modern impact of his breakthrough.
The correct order follows a clear chronological and logical progression. The passage begins with the paragraph establishing the historical mystery and the prevailing consensus that the Maya script was ideographic. The second paragraph transitions by referencing 'This scholarly consensus' and introducing Knorozov's counter-proposal of a phonetic script. The third paragraph transitions by stating 'To test this phonetic hypothesis,' detailing Knorozov's work with the Landa manuscript. The final paragraph concludes by showing how, 'Despite initial resistance,' the phonetic approach revolutionized the field and leads to the present-day status where epigraphers can read the majority of the texts.

Step-by-Step Solution

1
Identify the introductory paragraph.
The paragraph beginning with 'For centuries' introduces the ancient Maya script mystery and the early scholarly belief that the glyphs were ideographic. This sets up the context for the entire passage and must come first.
An introductory paragraph typically introduces the main subject and provides historical context without relying on preceding referents.
2
Connect the next paragraph using the referent 'This scholarly consensus'.
The paragraph starting with 'This scholarly consensus remained unchallenged' must follow the introduction, as it directly refers to the consensus of early scholars who believed the script was ideographic.
Transitions often rely on demonstrative pronouns ('this', 'these') that must refer to a noun or concept introduced in the immediate prior sentence or paragraph.
3
Connect the testing of the theory using the referent 'this phonetic hypothesis'.
The paragraph starting with 'To test this phonetic hypothesis' must follow the second paragraph, which ends with Knorozov's proposal that the script used 'phonetic signs representing individual syllables.'
The reference to 'this phonetic hypothesis' cannot logically occur until after the hypothesis itself has been explicitly introduced.
4
Identify the concluding paragraph detailing the outcome.
The paragraph starting with 'Despite initial resistance' describes the ultimate success of Knorozov's method and its modern-day results ('Today, because of this breakthrough...'). This provides a logical resolution to the narrative.
A concluding paragraph wraps up the discussion of a historical development by describing its long-term impact and present-day status.

Key Concept

Identifying logical relationships and cohesive transitions between paragraphs using cohesive devices, demonstrative referents, and chronological progression.
Estimated Time:2m 0s
Question 978Question

[1] __________________________________________________

[2] In 1964, radio astronomers Arno Penzias and Robert Wilson were employing an ultra-sensitive horn antenna at Bell Laboratories to analyze radio signals from the spaces between galaxies. However, their measurements were repeatedly disrupted by a persistent, low-frequency buzz that registered in their receiver. Despite washing the antenna, evicting a nesting pair of pigeons, and rebuilding the electrical components, the static remained completely unchanged. This mysterious hiss, which was eventually recognized as the cosmic microwave background radiation, provided the first concrete evidence of the Big Bang, transforming our understanding of the universe's origin.

Which choice most effectively introduces the passage by establishing its central focus on how a major cosmological breakthrough arose from an unexpected experimental obstacle?

Show answer & explanation

Answer: Science often progresses through accidental discoveries, where researchers searching for one phenomenon stumble upon another that reshapes our view of the cosmos.

Answer

Science often progresses through accidental discoveries, where researchers searching for one phenomenon stumble upon another that reshapes our view of the cosmos.
The correct answer effectively introduces the passage by highlighting that scientific progress often occurs through accidental discoveries. This sets up the discussion of how Penzias and Wilson stumbled upon the cosmic microwave background radiation while attempting to troubleshoot an unexpected buzz in their equipment, perfectly aligning with the rhetorical goal of the prompt.

Step-by-Step Solution

1
Analyze the prompt's rhetorical goal to identify the key elements required in the introduction.
The introduction must focus on a major cosmological breakthrough arising from an unexpected experimental obstacle.
Understanding the specific constraint in the prompt is crucial for selecting the correct choice.
2
Evaluate the options for grammatical correctness, eliminating any choices that contain sentence structure or punctuation errors.
The option starting with 'While searching' is eliminated due to a dangling modifier, and the option starting with 'Bell Laboratories' is eliminated due to a semicolon fragment.
ACT English questions require standard written English, so grammatically incorrect options must be eliminated.
3
Compare the remaining grammatically correct options against the rhetorical goal established in the first step.
The option discussing accidental discoveries aligns with the theme of an unexpected obstacle leading to a breakthrough, whereas the option discussing complex theoretical models is off-topic.
The correct choice must satisfy both grammatical standards and the specific rhetorical goal of the introduction.

Key Concept

Establishing Introductions and Thesis Statements
Estimated Time:1m 15s
Question 979Question

The writer wants to add the following sentence to the paragraph:

'After completing this initial step, they activated a digital timer to measure the speed of the dye's expansion.'

[1] To begin the experiment, the researchers placed a single drop of the blue dye onto the agar plate. [2] The solution immediately began to spread outward in a concentric circle. [3] Within minutes, the dye had completely disappeared, leaving the gel clear once again. [4] This rapid absorption surprised the team, who had expected the process to take much longer.

To make the paragraph most logical, where should this sentence be placed?

Show answer & explanation

Answer: after Sentence 1

Answer

after Sentence 1
The correct choice is the option that places the sentence after Sentence 1. Sentence 1 describes the first step of the experiment: placing a drop of dye. The target sentence refers back to 'this initial step' and introduces starting a timer, which logically fits before Sentence 2 describes the dye beginning to spread.

Step-by-Step Solution

1
Analyze the target sentence to find logical or transition clues.
The target sentence contains the phrase 'this initial step', indicating it must follow a sentence that describes the first action of the process.
Demonstrative pronouns and phrases require clear, preceding antecedents to establish logical continuity.
2
Locate the sentence describing the initial action in the paragraph.
Sentence 1 describes the first step of the experiment: placing a single drop of blue dye onto the agar plate.
This establishes that the target sentence must be placed after Sentence 1.
3
Verify chronological order with the remaining sentences.
Activating the timer to measure the speed of expansion must occur before the expansion actually begins in Sentence 2 and finishes in Sentence 3.
Ensuring the sequence of events flows chronologically prevents logical contradictions in the text.

Key Concept

Using demonstrative phrase pointers and chronological sequences to determine the logical placement of sentences.
Estimated Time:45s
Question 980Question

Ada Lovelace was a pioneering nineteenth-century mathematician who is widely celebrated for writing the world's first computer algorithm. [1] For example, she did not live to see a physical machine run her code, as the Analytical Engine was never completed during her lifetime.

Which choice provides the most logical transition between the first and second sentences?

Show answer & explanation

Answer: However,

Answer

However,
The correct option correctly uses a transition word that establishes a contrast relationship. The first sentence highlights Ada Lovelace's achievement of writing the first computer algorithm, while the second sentence contrasts this by explaining that she did not live to see it run on a physical machine.

Step-by-Step Solution

1
Analyze the logical relationship between the first and second sentences.
The first sentence describes Ada Lovelace's major achievement of writing the first computer algorithm. The second sentence describes a limitation or setback: she never saw her code executed on a physical machine.
Identifying the relationship between the sentences determines what category of transition is needed.
2
Determine the transition category that best connects these ideas.
Since the second sentence qualifies or presents a contrast to the achievement in the first, a contrast transition (like 'however') is required.
Choosing the correct category ensures logical cohesion in the passage.
3
Evaluate the choices to find the contrast transition.
The option providing 'However,' is the only one that expresses contrast. The other options establish illustration, addition, or cause-and-effect, which are logically incorrect.
This step verifies the correct option based on the logical analysis.

Key Concept

Selecting logical sentence transitions
Estimated Time:45s
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