영어 모의고사 (자동 편성)

Researchers who ①study teenagers have found a strong link between how well students sleep and how well they perform in school. Students who sleep fewer than seven hours a night tend to score lower on tests of memory and attention than those who ②sleep eight or nine hours, even when the two groups study for the same number of hours. One explanation is that sleep plays an active role in learning: during certain stages of sleep, the brain replays and strengthens information ③encountered during the day, converting fragile short-term memories into more durable long-term ones. When sleep is cut short, this consolidation process is interrupted before it can finish, so material that seemed well understood the night before often ④feel 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 ⑤could.

VO2 max, defined as the maximum volume of oxygen a person's body can consume and use during intense exercise, is widely regarded as one of the best single indicators of cardiorespiratory fitness. Elite endurance athletes typically post VO2 max values far ①higher than those of untrained individuals, reflecting hearts that pump larger volumes of blood and muscles that extract oxygen from that blood with remarkable efficiency. While genetics accounts for a substantial portion of an individual's potential VO2 max, consistent aerobic training can still ②raise the measurement considerably over months of dedicated effort. Interval training, which alternates short bursts of near-maximal effort with periods of recovery, has proven particularly ③effective at improving this measurement compared to steady, moderate-intensity exercise alone. It is worth noting, however, that a high VO2 max does not guarantee success in competition, since factors such as running economy, pacing strategy, and mental resilience also play a ④decisive role in determining who actually crosses the finish line first. These additional factors remain ⑤irrelevant to overall performance.

For centuries, dreams have ①fascinated scientists and philosophers alike, yet no single theory fully explains why the sleeping brain generates such vivid and often bizarre experiences. One prominent idea suggests that dreaming helps the brain process emotional experiences, replaying difficult events in a ②safe, low-stakes environment so that their emotional intensity gradually fades. Another theory proposes that dreams serve a more practical function, allowing the brain to ③ignore responses to threats without any real danger, a kind of nightly simulation that may have offered early humans a survival advantage. Still other researchers argue that dreaming is simply a byproduct of the brain organizing memories, with vivid imagery arising as the mind sorts through the day's ④information rather than serving any independent purpose of its own. Because these theories rest on indirect evidence, none has been ⑤conclusively proven.

When people consistently sleep too little, the body's hormonal balance shifts in ways that can ①quietly encourage weight gain. Two hormones in particular play ②opposing roles in regulating appetite: leptin signals fullness to the brain, while ghrelin stimulates the sensation of hunger. Studies show that sleep deprivation lowers leptin levels while raising ghrelin levels, so a tired body ends up feeling ③fuller than it actually needs to be, even after a normal-sized meal. At the same time, insufficient sleep interferes with how efficiently the body processes glucose, making cells less ④responsive to insulin and leaving more sugar circulating in the bloodstream than usual. Over months or years, this combination of increased appetite and reduced insulin sensitivity can contribute to steady weight gain and raise the risk of developing type 2 diabetes. Because these effects build up so ⑤gradually, many people never connect their shifting eating habits or worsening blood sugar to something as ordinary as a few lost hours of sleep each night.

Only a decade ago, translation apps produced sentences so awkward that users often laughed at the results. Today, many of these apps rely on neural networks that analyze entire sentences at once, capturing context instead of translating word by word. This shift has made everyday tasks such as reading a foreign menu or chatting with an overseas friend remarkably smooth. Even so, the technology still struggles with humor, sarcasm, and cultural nuance, so that _______________. For this reason, professional translators argue that these apps are best treated as a helpful starting point rather than a final, polished result.

Exercise does far more than strengthen muscles and the heart; it also produces measurable changes within the brain itself. During sustained physical activity, the body releases a protein called brain-derived neurotrophic factor, which supports the growth of new neurons and strengthens connections between existing ones, particularly in regions associated with memory and learning. Studies comparing physically active students to sedentary peers have repeatedly found that _______________, even when the exercise session ends well before the test begins. Researchers believe that exercise increases blood flow to the brain, delivering oxygen and nutrients more efficiently, while also reducing levels of stress hormones that can interfere with clear thinking.

Wearable devices that track sleep have become enormously popular, promising a detailed breakdown of light, deep, and REM sleep each night. (A) Despite these limitations, many users have come to treat the nightly score generated by their device as an objective medical verdict, sometimes experiencing anxiety when the number falls below what they expect, a phenomenon researchers have begun calling orthosomnia. (B) Independent studies comparing wearable data with polysomnography, the gold-standard method used in clinical sleep labs, have found that consumer devices are reasonably accurate at distinguishing sleep from wakefulness but considerably less reliable at identifying specific sleep stages. Some trackers overestimate deep sleep, while others underestimate the amount of time spent in REM sleep, and the margin of error can vary widely between brands. (C) These gadgets typically rely on movement sensors and heart rate monitors to estimate sleep stages, since directly measuring brain activity would require equipment found only in a sleep laboratory. This indirect approach, however, introduces significant uncertainty.

Open a music streaming app on any given morning, and a personalized playlist is usually already waiting, assembled overnight from songs the algorithm predicts will match a listener's current mood. (A) Musicians, meanwhile, have mixed feelings about this shift, since a song the algorithm decides not to promote may struggle to reach listeners no matter how well it was written. (B) Listeners often praise the feature for introducing them to artists they never would have searched for on their own, effectively acting as a tireless music scout working around the clock. (C) This prediction relies on far more than genre alone; the system studies skip rates, replay counts, and even the time of day a song is typically played to build a detailed profile of individual taste.

Feed an AI music program a mood, a tempo, and a rough genre, and within seconds it can generate a complete instrumental track. (A) The software has studied thousands of existing songs, learning which chord progressions and rhythms tend to sound pleasant together, and it recombines these patterns into something new. (B) For independent creators who cannot afford a composer or expensive licensing fees, this has been a genuine breakthrough. (C) Professional musicians, however, remain divided, since a flood of AI-generated background music could quietly push human composers out of smaller, lower-budget projects.

주어진 문장: In other words, those who did the least to cause the problem often end up paying the highest price for it. When people discuss climate change, they often focus only on rising temperatures or melting ice, treating it as a purely scientific issue. ( ① ) However, the concept of climate justice reminds us that the causes and consequences of climate change are distributed unevenly across the globe. ( ② ) Wealthy, industrialized nations have historically released the largest share of greenhouse gases while building their economies, yet developing nations, which contributed comparatively little, frequently suffer the most severe droughts and floods. ( ③ ) This gap between responsibility and suffering raises a serious ethical question that science alone cannot answer. ( ④ ) For example, a farming community in a low-income country may lose its entire harvest to an unusual flood, even though its members have never owned a car or flown on a plane. ( ⑤ ) Therefore, tackling climate change requires more than new technology; it demands fair policies supporting the very communities least responsible for causing the crisis.