영어 모의고사 (자동 편성)

Browsing an online store today often means ① chatting with an AI assistant that asks a few quick questions, such as budget or intended use, before suggesting a short list of products tailored to the answers. Unlike a static list of best-sellers, this assistant can adjust its suggestions on the spot, ② responding to follow-up questions the way a knowledgeable salesperson might in a physical store. Retailers report that shoppers ③ who use these chatbots tend to complete purchases more often and return fewer items, since the guided conversation helps buyers choose products that actually fit their needs. Some shoppers, however, remain wary of how personal the questions can feel, ④ wonder how much of that conversation is quietly stored and reused to influence future purchases. Consumer advocates argue that stores should clearly explain what happens to this data, rather than ⑤ burying the explanation in a lengthy privacy policy.

Climate scientists frequently warn about tipping points, thresholds beyond which a small additional change ①triggers a large, often irreversible shift in the climate system. Unlike gradual warming, which unfolds steadily over decades, crossing a tipping point can produce dramatic consequences within a short period. For instance, as Arctic ice melts, it exposes darker ocean water that ②absorb more sunlight than reflective ice, accelerating further melting in a self-reinforcing cycle. Similarly, scientists worry that a major ocean current, which currently ③redistributes heat across the planet, could slow dramatically if enough freshwater from melting glaciers dilutes the surrounding seawater. Once such thresholds are crossed, ④restoring the original balance may become nearly impossible, even if emissions are later reduced. Therefore, researchers argue that preventing these transitions ⑤matters more than merely slowing average temperature increases.

A flexitarian is someone who mainly eats plant-based meals but occasionally includes meat or fish, unlike a ①strict vegetarian who avoids animal products entirely. This flexible diet has recently ②lost attention as a practical way to fight climate change, since raising livestock produces a ③significant portion of global greenhouse gas emissions. Cattle, in particular, release large amounts of methane, a gas far more powerful than carbon dioxide at trapping heat in the atmosphere. By replacing just a few meat-based meals each week with vegetables, grains, or legumes, individuals can ④noticeably shrink their carbon footprint without giving up meat completely. Nutritionists also emphasize that flexitarian eating is easier to maintain than full vegetarianism, because it allows flexibility rather than demanding absolute discipline. Therefore, many environmental groups now promote flexitarianism as a ⑤realistic first step, believing that gradual change, rather than sudden restriction, is more likely to spread widely across society.

Across many countries, high schools begin classes early in the morning, often before eight o'clock. This schedule assumes that teenagers can simply go to bed earlier to compensate, but biology tells a different story. During adolescence, the body's internal clock shifts later, delaying the release of melatonin until well after ten at night. As a result, most teenagers are not physiologically ready to fall asleep until much later than younger children or adults. When early start times force them to wake before their bodies have completed a full sleep cycle, the mismatch accumulates into a chronic sleep debt that affects concentration and mood throughout the school day. Researchers who study this mismatch argue that _______________. Some school districts that delayed their start times by thirty minutes reported improvements in attendance, suggesting that the timing of the school day matters more than commonly assumed.

Sleep debt refers to the cumulative gap between the amount of sleep a person needs and the amount they actually get. Unlike a financial debt, however, this deficit cannot simply be repaid with a single long weekend of rest. When someone loses two hours of sleep every night for a week, the body does not treat the shortage as fourteen separate small losses; instead, it accumulates the deficit, and _______________. Researchers have found that even modest, chronic sleep restriction gradually impairs reaction time and decision-making, often without the affected person noticing the decline. This is because subjective feelings of tiredness tend to plateau after a few days, even as objective performance keeps deteriorating. Consequently, people frequently underestimate how much sleep debt they are carrying until a demanding task suddenly exposes the accumulated cost.

Many companies now advertise themselves as environmentally responsible, yet a growing number of these claims turn out to be misleading. This practice, known as greenwashing, _______________. A company might launch a recycled-packaging line while continuing to pollute rivers through its main factories, creating a false impression of genuine change. Such tactics deceive well-intentioned consumers who wish to shop responsibly but lack the tools to verify corporate claims. In contrast, truly sustainable businesses publish detailed, independently verified data about their emissions and supply chains, allowing outsiders to check their progress. Therefore, shoppers should look beyond vague labels like green or natural and instead search for recognized certifications, transparent reports, and measurable targets. Without such scrutiny, greenwashing will keep flourishing, undermining public trust and slowing the broader shift toward an economy that truly protects the planet.

Insomnia is rarely caused by a single factor; it usually emerges from an interaction between psychological stress and physiological arousal that keeps the body from settling into sleep. (A) At the same time, the body's stress response system can become chronically activated, releasing hormones such as cortisol that keep heart rate and body temperature elevated at night, both of which interfere with the natural drop in arousal needed to fall asleep. (B) Poor sleep habits, including irregular bedtimes and excessive screen use before bed, can further weaken the body's internal signals for sleep onset. Because these psychological and physiological factors reinforce one another, effective treatment for chronic insomnia addresses both the racing mind and the underlying pattern of physical tension, rather than relying on medication alone. (C) A common trigger is what researchers call cognitive hyperarousal, in which the mind continues to race with worries about work, relationships, or even the inability to sleep itself, creating a frustrating cycle where anxiety about insomnia becomes a cause of insomnia.

Researchers who study teenagers have found a strong link between how well students sleep and how well they perform in school. (A) Students who sleep fewer than seven hours a night tend to score lower on tests of memory and attention than those who sleep eight or nine hours, even when the two groups study for the same number of hours. (B) One explanation is that sleep plays an active role in learning: during certain stages of sleep, the brain replays and strengthens information encountered during the day, converting fragile short-term memories into more durable long-term ones. (C) When sleep is cut short, this consolidation process is interrupted before it can finish, so material that seemed well understood the night before often feels unfamiliar the next morning. For this reason, some schools have begun rethinking early start times, reasoning that an extra hour of sleep might do more for test scores than an extra hour of studying ever could.

This is precisely what makes the condition so difficult to catch before it becomes severe. Ambitious young athletes and the parents who support them sometimes assume that more training automatically produces better results, a belief that occasionally leads to a condition known as overtraining syndrome. ( ① ) Unlike ordinary fatigue that resolves after a few days of rest, overtraining syndrome develops gradually over weeks or months of insufficient recovery relative to training load, eventually producing persistent exhaustion, declining performance despite continued hard work, and increased susceptibility to illness and injury. ( ② ) Adolescents may be especially vulnerable, since their bodies are simultaneously coping with the physical demands of growth and the added stress of intensive training schedules. ( ③ ) Warning signs are often subtle at first, including disrupted sleep, irritability, and a loss of enthusiasm for a sport the athlete once genuinely enjoyed, which adults often mistake for ordinary moodiness. ( ④ ) Recovery from full-blown overtraining syndrome can take months rather than days. ( ⑤ )

This connection is not merely correlational; sleep appears to directly supply the raw materials the immune system needs. When the body fights off an infection, the immune system relies heavily on adequate sleep to function effectively. ( ① ) During deep sleep, the body produces and releases cytokines, proteins that help regulate immune responses and coordinate the fight against harmful invaders such as viruses and bacteria. ( ② ) People who consistently sleep fewer than six hours a night show measurably weaker antibody responses after vaccination compared with those who sleep seven or eight hours, suggesting that sleep loss can blunt the immune system's ability to build lasting protection. ( ③ ) Chronic sleep deprivation also appears to promote low-grade inflammation throughout the body, a state that, over time, has been linked to a higher risk of heart disease and other chronic conditions. ( ④ ) Rather than being a passive state in which the body simply rests, sleep functions as an active period during which the immune system repairs itself and prepares for future threats. ( ⑤ ) This is why doctors often recommend extra sleep, not just medication, when someone is fighting an illness.