영어 모의고사 (자동 편성)

Time travel to the past has long fascinated physicists and philosophers alike, but it also ①generates a famously troubling contradiction. Suppose a traveler journeyed backward in time and, through some combination of accident and intention, ②prevented their own grandfather from ever meeting their grandmother. If the grandfather never had children, the traveler themselves would never have been born, which means the traveler could never ③existed to make the trip in the first place. Yet if the traveler never made the trip, the grandfather would have survived to meet the grandmother after all, ④allowing the traveler to be born and eventually travel back in time. The story therefore loops endlessly, undermining itself at every turn rather than ⑤settling into any stable outcome.

Working memory refers to the mental workspace in which information is ①temporarily held and manipulated while a person performs a cognitive task. Such tasks include solving an arithmetic problem, following a rapid conversation, or holding a phone number in mind before dialing it. In the mid-twentieth century, the psychologist George Miller proposed that this workspace could accommodate roughly seven discrete items. His claim proved so ②influential that it became widely known as the magic number seven. Subsequent research, however, revealed that Miller's estimate was somewhat ③conservative, since it failed to account for the complexity of the material being remembered. Nelson Cowan later argued that when rehearsal strategies are ④prevented and attention is tightly controlled, genuine capacity hovers closer to four items rather than seven. This discrepancy suggests that what earlier studies had measured was not raw storage capacity itself but a hybrid quantity ⑤inflated by clever strategies. Contemporary psychologists therefore distinguish between the fixed limit of working memory and the flexible techniques that allow individuals to transcend that limit.

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.

A printer that once produced only plastic prototypes can now deposit living cells layer by layer to build a structure that begins to ①resemble actual tissue. Bioprinting adapts the logic of conventional 3D printing, replacing plastic filament with a ②specialized ink made of living cells suspended in a gel that supports their survival while the shape sets. Printing a flat patch of skin or a simple blood vessel has already moved from laboratory curiosity to early clinical testing, since these tissues are thin enough for nutrients to reach every cell by ③diffusion. Printing a solid organ such as a kidney remains a far greater challenge, because internal cells ④thrive without their own blood supply, and no printer yet exists that can build a network of vessels fast enough to keep them alive. Researchers are therefore focusing on hybrid strategies, printing a rough scaffold and then allowing the tissue to mature and grow its own vasculature over ⑤time.

Medieval philosophers told the story of a hungry donkey placed exactly midway between two identical, equally fragrant piles of hay, with no factor whatsoever tipping the balance toward either option. Because the donkey is assumed to be a perfectly ①rational creature that always chooses the option supported by the strongest reason, and because neither pile offers any advantage over the other, the donkey supposedly finds itself with no rational basis for choosing one pile rather than the other. ②Paralyzed by this perfect symmetry, the donkey starves to death precisely because it can find no reason to move in either direction. Critics of the story point out that real animals, and real humans, rarely face situations of such flawless symmetry, and that even a tiny, ③arbitrary preference is usually enough to break the tie in practice. The paradox nevertheless raises a serious question about whether purely rational deliberation can ever ④generate action on its own, without some additional nudge that reason alone ⑤willingly supplies.

A hamburger patty need not come from a slaughtered animal if a small sample of muscle cells can be persuaded to multiply inside a steel tank. Cultured meat begins with a biopsy of animal muscle tissue, from which scientists isolate cells capable of dividing repeatedly, then feed those cells a nutrient broth that supplies the sugars, proteins, and minerals an animal's bloodstream would normally provide. Inside a bioreactor, the cells multiply across scaffolding designed to encourage them to align into fibers, gradually thickening into something that begins to resemble muscle tissue. Supporters argue that because the process never requires raising and slaughtering a whole animal, _______________. Skeptics counter that producing the specialized broth at a large enough scale remains prohibitively expensive, meaning cultured meat is unlikely to compete with conventional meat in price until the technology matures considerably further.

Suppose a mysterious being with a near-perfect track record of predicting human choices presents a player with two boxes. (A) The player may choose to take only Box B, or to take both boxes, and the prediction has already been made and cannot change. (B) Box A always contains a visible thousand dollars, while Box B contains either a million dollars or nothing at all, depending on a prediction the being made before the game even began. (C) One line of reasoning says taking both boxes is strictly better, since whatever is already inside the boxes cannot be altered by the player's choice at this point, while a second line of reasoning says taking only Box B is better, given the being's near-perfect accuracy.

A single fertilized egg eventually gives rise to every cell type in the human body, from neurons to bone, a feat that has fascinated biologists for more than a century. (A) Because harvesting these cells traditionally required destroying a human embryo, the research provoked ethical objections fierce enough to slow funding and legislation in several countries for years. (B) A breakthrough arrived when scientists discovered that ordinary adult skin cells could be reprogrammed into a state resembling embryonic versatility without ever touching an embryo, opening a path for stem cell research that far more scientists and funding agencies are now willing to support. (C) Embryonic stem cells retain much of that original versatility, capable in principle of developing into almost any tissue, which is why researchers have long viewed them as a promising raw material for repairing damaged organs.

The cell then acts as a temporary factory, translating that instruction into an actual protein without ever altering the cell's permanent genetic code. For decades, most vaccines worked by injecting a weakened or inactivated version of a pathogen, coaxing the immune system into recognizing an enemy it had never truly fought. ( ① ) mRNA vaccines take a fundamentally different 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. ( ② ) Once those cells display the fragment, the immune system learns to recognize it as foreign and builds a defense, without ever having encountered the actual pathogen. ( ③ ) Because the vaccine contains no live virus and cannot alter a cell's own DNA, developers can redesign the genetic instructions within weeks whenever a pathogen mutates. ( ④ ) This is far shorter than the years-long process required for traditional vaccines. ( ⑤ ) This speed, first proven on a global scale during a recent pandemic, has convinced many researchers that the same platform could eventually be adapted to fight diseases far beyond infectious illness, including certain cancers.

In other instances, the danger came not from the immune system at all but from where the new gene happened to land. For patients born with a single faulty gene, the disease has traditionally been treated indirectly, managing symptoms for a lifetime rather than addressing the genetic error itself. ( ① ) Gene therapy attempts something more ambitious: delivering a corrected copy of the gene directly into a patient's cells, often using a disabled virus stripped of its ability to cause illness as a delivery vehicle. ( ② ) Once inside the nucleus, the corrected gene can begin producing the protein the patient's body had always lacked, in some cases reversing symptoms that medication alone had never been able to touch. ( ③ ) Early trials were haunted by serious setbacks, including cases in which the delivery virus triggered a dangerous immune reaction. ( ④ ) The virus, in such cases, inserted the new gene in a spot that disrupted other essential genes. ( ⑤ ) Refined delivery methods have since made the treatment considerably safer, and regulators in several countries have now approved gene therapies for a small but growing number of rare inherited disorders.