영어 모의고사 (자동 편성)

Long before humans learned to drill for oil, microorganisms had already ①mastered the art of converting sunlight and carbon dioxide into stored chemical energy. Modern biofuel research borrows this ability, cultivating algae or engineered bacteria in large tanks where they can be coaxed into producing oils and sugars that can be ②refined into fuel usable in existing engines. Unlike crops grown for corn-based ethanol, which ③compete directly with food production for arable land, many algae strains can thrive in shallow ponds, wastewater, or even coastal seawater unsuitable for conventional agriculture. Engineers have also learned to tinker with the metabolic pathways of these organisms, boosting oil yield far beyond what any wild strain would naturally produce on its own. Despite this progress, producing biofuel at a cost competitive with fossil fuel remains ④difficult, since harvesting and processing the organisms ⑤conserves a substantial share of the energy the fuel itself will eventually provide.

For decades, most vaccines worked by injecting a ①weakened or inactivated version of a pathogen, coaxing the immune system into recognizing an enemy it had never truly fought. mRNA vaccines take a fundamentally ②different route, delivering only a short genetic instruction wrapped in a protective lipid capsule, one that tells the body's own cells how to manufacture a single harmless piece of a virus's outer surface protein. Once those cells display the fragment, the immune system learns to recognize it as ③foreign and builds a defense, without ever having encountered the actual pathogen. Because the vaccine contains no live virus and cannot alter a cell's own DNA, developers can ④redesign the genetic instructions within weeks whenever a pathogen mutates, rather than starting the years-long process required for traditional vaccines. This speed has convinced many researchers that the same platform could eventually be adapted to fight diseases far beyond infectious illness, ⑤excluding certain cancers.

As efforts to ①curb greenhouse gas emissions intensify, industries unable to eliminate carbon dioxide from their processes have turned to a technology known as carbon capture and storage. This technology involves separating carbon dioxide from the exhaust of power plants before it is released into the atmosphere, then transporting the captured gas for underground injection. Once injected into porous rock formations, the gas is trapped beneath layers of impermeable rock that prevent it from escaping into the air. Proponents argue that carbon capture and storage functions as a bridge technology, allowing heavy industries to keep operating while more sustainable alternatives are ②developed. For instance, cement and steel production, both of which release carbon dioxide as an ③unavoidable byproduct of chemical reactions, are considered prime candidates for this approach. However, critics contend that the technology remains prohibitively ④cheap and that building pipelines requires investments few companies make voluntarily. Despite such concerns, many governments continue funding pilot projects, convinced that this technology will play an ⑤indispensable role in reaching emission targets.

As more schools shift toward digital textbooks and online assignments, a student without reliable internet access at home faces a disadvantage that has little to do with talent or effort. (A) That assumption is increasingly being reconsidered, particularly as more essential services, from job applications to medical appointments, move online by default. (B) Some policymakers initially treated internet access as a convenience, comparable to cable television, rather than as infrastructure essential to modern life. (C) Closing this divide will require more than simply distributing devices; it will demand sustained investment in the physical networks that carry information into every home.

The influence of the status quo bias extends well beyond personal finance into the design of public policy itself. (A) Consequently, policymakers who wish to encourage socially beneficial behavior, such as organ donation or energy conservation, have increasingly turned to adjusting default settings rather than relying solely on persuasion or financial incentives. (B) Countries that changed their organ donation systems from opt-in to opt-out, for example, observed dramatic increases in the proportion of citizens registered as donors, without any change in the underlying laws governing consent. (C) This outcome demonstrates that the default option itself functions as an implicit recommendation, one that citizens are reluctant to override even when doing so would take only a moment.

Among the many strategies proposed to remove carbon dioxide from the atmosphere, one of the oldest draws on an agricultural technique predating modern industry, converting organic material into a stable form of charcoal known as biochar. (A) When mixed into farmland, biochar also improves soil structure, retaining moisture and nutrients otherwise lost, which can boost crop yields in depleted soils. For example, farmers cultivating nutrient-poor tropical soils have reported measurable increases in productivity after adding biochar. (B) Biochar is produced through pyrolysis, a process in which crop residues or wood chips are heated in an environment with little or no oxygen, preventing the material from burning away as in an open fire. This process leaves behind a carbon-rich solid that resists decomposition far longer than raw organic matter, locking carbon in a form remaining stable in soil for centuries. (C) Nevertheless, researchers caution that the climate benefits of biochar depend on the feedstock and method used, since poorly managed pyrolysis can release as much carbon as it sequesters, undermining its own purpose.

The discovery of CRISPR gene-editing technology gave scientists a tool precise enough to correct a single mistaken letter in the human genome, raising hope for curing inherited diseases. (A) Scientific organizations around the world have therefore drawn a careful line, permitting gene editing to treat disease in existing patients while banning any edit that would be inherited by their descendants. (B) Yet editing a gene in a sperm, egg, or early embryo does not simply change one patient; it alters the genetic code passed down to every future generation. (C) Critics worry, however, that as the technology becomes cheaper and more widely available, this line will become harder to enforce than it is to draw.

When a resource is shared among many users, none of whom bears the full cost of its depletion, each individual is tempted to extract as much value as possible before others do the same. (A) This dynamic, famously labeled the tragedy of the commons, describes how shared pastures and fisheries can be degraded even when every participant privately understands the danger of overuse. (B) A single herder who adds one more animal to a communal pasture gains the entire benefit of that addition, whereas the resulting damage to the grass is shared among other herders who depend on the land. Because self-interest offers no incentive to restrain consumption unilaterally, the resource tends to be exhausted long before any user intends such an outcome. (C) For decades, economists assumed that only two remedies existed: strict regulation or the conversion of shared resources into private property. Elinor Ostrom challenged this assumption, however, by documenting communities that had sustainably managed fisheries and forests for generations through locally devised rules and mutual monitoring rather than external control.

A society is often judged by how much intergenerational mobility it permits, since high mobility suggests that outcomes depend more on effort and ability than on the accident of birth. Social mobility refers to the movement of individuals or families between different positions within a society's system of stratification, whether upward, downward, or sideways. ( ① ) Sociologists distinguish intragenerational mobility, changes within a single person's lifetime, from intergenerational mobility, differences between the social position of parents and their children. ( ② ) Structural mobility, caused by large-scale economic shifts such as the growth of new industries, must be distinguished from individual mobility, which results from a single person's particular choices. ( ③ ) Research across many nations has found that education functions as the primary channel of upward mobility. ( ④ ) Yet access to quality education is itself unevenly distributed, meaning the very mechanism meant to promote fairness can end up reproducing the inequality it was designed to overcome. ( ⑤ )

Scarcity cues of this kind are becoming increasingly common across online retail platforms, appearing on everything from hotel bookings to concert tickets. A shopper browsing an online store notices that a particular item is marked as "only three left in stock." ( ① ) Before seeing this notice, the shopper had regarded the item with only mild interest, uncertain whether it was worth purchasing at all. ( ② ) After seeing the notice, however, the same shopper suddenly feels a pressing urge to complete the purchase before the remaining stock disappears, even though nothing about the item itself has changed. ( ③ ) This shift in urgency illustrates how scarcity cues can transform hesitation into immediate action within moments. ( ④ ) Retailers are well aware of this dynamic, which is why such notices frequently appear even when actual stock levels are difficult for customers to verify independently. ( ⑤ ) Whether the stated scarcity is genuine or exaggerated, its psychological effect on the shopper's behavior remains remarkably similar.