영어 모의고사 (자동 편성)

Sleep is not a single, uniform state but a cycle that alternates between two very different modes: REM (rapid eye movement) sleep and non-REM sleep. During non-REM sleep, especially its deepest stage, the brain waves slow down dramatically, the body temperature drops, and tissue repair and growth hormone release reach their peak. This is the period ①most closely associated with physical restoration. REM sleep, by contrast, brings rapid eye movements, near-total muscle paralysis, and brain activity that closely ②resemble wakefulness. Most vivid dreaming occurs during this stage, and researchers believe it ③plays a central role in consolidating memories and processing emotional experiences. A healthy night typically cycles through both stages four or five times, with non-REM ④dominating the early hours and REM periods lengthening toward morning. Disrupting either stage, through frequent awakenings or alcohol use, can leave a person ⑤feeling unrested even after a full night in bed.

Athletes preparing for major endurance events sometimes ①trains for weeks at high altitude, where the air contains less oxygen than at sea level, in hopes of gaining a physiological edge once they return to compete at lower elevations. In this thin air, the body responds by producing more red blood cells, ②which carry oxygen more efficiently through the bloodstream to working muscles. When these athletes return to sea level, where oxygen is more abundant, their blood ③retains this elevated capacity for a limited period, potentially translating into improved endurance performance. However, the benefits of altitude training are far from guaranteed, since individual athletes respond quite differently to the same conditions, and some experience excessive fatigue that ④undermines the very training they hoped to complete. Many elite programs therefore follow a strategy known as live high, train low, in which athletes sleep at altitude to stimulate blood adaptations but perform intense workouts at lower elevation ⑤to maintain quality and intensity.

A smartwatch strapped to a runner's wrist can now do far more than simply count steps; it monitors heart rate variability, running form, and recovery time, then uses that data ①to suggest a training plan tailored to the individual rather than a generic weekly schedule. When the device detects signs of overtraining, such as an unusually high resting heart rate several mornings in a row, it may recommend a lighter workout or an extra rest day before fatigue ②turns into an actual injury. Amateur athletes often credit this kind of guidance with ③help them train more consistently without pushing their bodies too hard. Sports scientists note an important caveat, however: a wrist-based sensor cannot fully capture the same physiological detail ④available in a professional lab, so its suggestions should be treated as a helpful guideline rather than an infallible medical judgment, particularly for anyone ⑤managing a chronic health condition.

Many companies now advertise themselves as environmentally responsible, yet a growing number of these claims ①turn out to be misleading. This practice, known as greenwashing, ②occurs when a business spends more effort marketing its products as eco-friendly than actually reducing environmental harm. A company might launch a recycled-packaging line while ③continuing 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 ④lacks the tools to verify corporate claims. In contrast, truly sustainable businesses publish detailed, independently verified data about their emissions and supply chains, ⑤allowing outsiders to check their progress.

The planning fallacy describes the tendency to ①underestimate how long a task will take, even when experience suggests otherwise. Psychologists who studied this bias found that people focus mainly on an ②idealized, best-case version of a project. They focus less on how similar projects actually unfolded before. Large construction projects offer another example. Officials frequently predict completion dates that later prove far too ③optimistic once delays appear. One reason this bias persists is that people ④rarely review their history of missed deadlines, relying instead on hopeful imagination. By anchoring predictions to real outcomes, planners can produce estimates that are considerably more ⑤inaccurate.

Time blocking is a time-management technique in which a person divides the day into fixed blocks. Each block is then assigned to a single task. Instead of relying on a loose to-do list, the person decides exactly when each task will start and end. This approach ①lowers the mental effort of deciding what to do next, since the schedule already provides the answer. It also ②limits multitasking, because each block is reserved for only one activity at a time. For instance, a student may block ninety minutes for math practice, leaving no room for messages or web browsing. Because each block has a ③vague boundary, unfinished work is ④less likely to quietly spread into the next task. Many people who adopt time blocking feel ⑤more organized throughout the day.

Browsing an online store today often means chatting with an AI assistant that asks a few quick questions, such as budget or intended use, before suggesting a short list of products ①tailored to the answers. Unlike a static list of best-sellers, this assistant can adjust its suggestions on the spot, responding to follow-up questions the way a knowledgeable salesperson might in a physical store. Retailers report that shoppers who use these chatbots tend to ②complete purchases more often and return fewer items, since the guided conversation helps buyers choose products that actually fit their needs. Some shoppers, however, remain ③confident about how personal the questions can feel, wondering how much of that conversation is quietly stored and reused to influence future purchases. Consumer advocates argue that stores should ④clearly explain what happens to this data, rather than ⑤burying the explanation in a lengthy privacy policy that almost no one reads.

Coaches have traditionally focused athlete preparation on training volume and nutrition, but a growing body of research suggests that sleep deserves equal attention. During deep sleep, the body releases growth hormone, a substance essential for repairing muscle tissue damaged during intense training, while the brain consolidates motor skills practiced earlier that day into more stable, efficient patterns. As a result, _______________. Frequent travel across time zones compounds this challenge considerably, since jet lag can disrupt an athlete's natural sleep-wake cycle for several days after a long flight, sometimes right before an important competition.

Social psychologists describe a phenomenon called the bystander effect, in which individuals become less likely to help a victim as the number of witnesses increases. Each observer assumes someone else will step in, and this diffusion of responsibility leaves no one willing to act. Cyberbullying magnifies this problem, since a single humiliating post can be witnessed by thousands of people scattered across the internet rather than a few standing nearby. Anonymity intensifies the effect further, allowing silent observers to scroll past cruel comments without feeling accountable for their inaction. Some bystanders even worry that intervening publicly might make them the bully's next target, so they choose to remain silent instead. However, silence signals approval to both the bully and the audience watching the exchange unfold. Experts insist that even a single supportive comment can disrupt this harmful pattern. Therefore, witnesses online must _______________.

Only a decade ago, translation apps produced sentences so awkward that users often laughed at the results rather than trusting them. (A) Frequent travelers now point their phone cameras at street signs and receive an instant translation overlaid on the screen, thanks to this leap in accuracy. (B) Even so, the technology still struggles with humor, sarcasm, and cultural nuance, areas where a single wrong word can completely change the intended meaning. (C) Today, many of these apps rely on neural networks that analyze entire sentences at once, capturing context instead of translating word by word.