영어 모의고사 (자동 편성)

Every cell in the human body follows an internal timer known as the circadian rhythm, a roughly twenty-four-hour cycle ① that governs when we feel alert and when we feel drowsy. This clock is regulated primarily by a tiny cluster of neurons in the brain ② that responds to light entering through the eyes. When morning sunlight strikes the retina, the cluster signals the body ③ to suppress sleep hormones and raise body temperature, preparing us for activity. As evening approaches and light fades, the same mechanism triggers the release of melatonin, a hormone ④ promotes drowsiness. Because this rhythm evolved around the natural cycle of day and night, modern habits such as staying indoors under artificial light or working night shifts can push the internal clock out of sync with the external environment. Such misalignment does not simply cause tiredness; it has also ⑤ been associated with digestive problems and reduced concentration, suggesting that timing matters as much as total sleep hours.

Anthropologist Robin Dunbar proposed a concept now known as Dunbar's number, suggesting that human beings can only ①abandon about one hundred fifty stable social relationships at any given time. This limit, he argued, comes from the size of the human brain, which ②restricts how many meaningful connections a person can cognitively manage. In contrast, many social media users today have hundreds or even thousands of online friends and followers, a number far ③exceeding what Dunbar's research predicts. However, having numerous digital contacts does not necessarily mean that all of these relationships are ④close or emotionally supportive. Most users, when asked, admit that they interact regularly with only a small fraction of their total followers, while the rest remain largely ⑤unnoticed.

Team sports place athletes in a uniquely social form of competition, one where individual skill alone ① rarely determines the outcome of a match. Sports psychologists have long studied why some groups of talented individual players fail to perform as a cohesive unit while other, less individually skilled teams consistently ② exceed expectations. Trust among teammates appears to be a ③ decisive factor, since players who believe their teammates will reliably fulfill their roles are more willing to take the calculated risks that winning often requires. Clear and consistent communication during high-pressure moments further reduces the hesitation and confusion that can ④ unravel a team's coordination in front of a crowd. Interestingly, researchers have found that teams which deliberately build informal social bonds off the field tend to display better on-field cohesion, suggesting that chemistry can ⑤ easily be manufactured through drills alone.

Smartphones, tablets, and computer screens all emit a significant amount of blue light, a short-wavelength light that our eyes are especially sensitive to. During the day, exposure to blue light from the sun helps keep us alert and mentally sharp, which is generally beneficial. At night, however, the same wavelength can interfere with the body's natural preparation for sleep. Specialized cells in the retina detect blue light and send signals to the brain's internal clock, which results in _______________. Studies have found that people who scroll through their phones in bed before sleeping take longer to fall asleep and experience lighter, more easily disrupted sleep than those who avoid screens. Some devices now offer a night mode that shifts the display toward warmer tones, reducing blue light output in the evening. While this feature may help slightly, sleep researchers generally recommend limiting screen use altogether in the hour before bedtime for the best results.

Some changes in habit begin not with a big decision but with a quiet moment that lingers in the mind. (A) That changed when her class was assigned a documentary about plastic waste drifting through the ocean, footage she initially expected to find boring. Instead, watching seabirds mistake plastic fragments for food left her strangely unsettled, and she found herself thinking about the assignment long after class ended. (B) The next morning, almost without deciding to, she slipped her old tumbler into her backpack instead of buying a disposable cup on the way to school. It felt like a small, meaningless gesture at first. However, as weeks passed, she realized that consistently choosing the tumbler, declining a plastic straw, and reusing a shopping bag were quietly adding up. Small choices, she discovered, become meaningful once repeated. (C) Until last spring, Minji rarely thought twice about tossing a paper cup into the trash after finishing her coffee. Environmental issues seemed distant, something scientists and politicians should handle rather than an ordinary student like her.

주어진 문장: In other words, working longer hours does not necessarily lead to better results if that time is spent in a low-energy state. For decades, productivity advice has focused almost entirely on managing time efficiently, yet many experts now argue this approach overlooks something important. ( ① ) This alternative approach, known as energy management, suggests that controlling personal energy matters more than controlling the clock. ( ② ) Unlike time, which flows at a constant rate, human energy naturally rises and falls in cycles shaped by sleep, food, and mental fatigue. ( ③ ) A person who tackles difficult tasks during a low-energy period, for instance, may need two hours to finish what takes thirty minutes at peak energy. ( ④ ) Similarly, someone who forces themselves to keep working without rest often produces careless mistakes that require additional time to correct later. ( ⑤ ) Advocates of energy management recommend identifying one's peak hours and reserving them for demanding work, while saving low-energy periods for routine tasks.

Yet the number displayed each morning is only as good as the estimate behind it. Wearable devices that track sleep have become enormously popular, promising a detailed breakdown of light, deep, and REM sleep each night. ( ① ) 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. ( ② ) This indirect approach, however, introduces significant uncertainty. ( ③ ) 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. ( ④ ) 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. ( ⑤ ) 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.

주어진 문장: In short, Fogg's model reminds us that ease of action, not sheer willpower, drives lasting behavior change. Many people believe that building a new habit requires strong willpower or motivation. ( ① ) However, psychologist BJ Fogg argues that habits form more easily when a behavior itself becomes simple to perform. ( ② ) His theory, called the Fogg Behavior Model, states that a behavior happens only when motivation, ability, and a prompt occur together. When motivation is low, the task must be made extremely easy, or it will not happen at all. ( ③ ) For instance, a person who wants to exercise daily succeeds more often by committing to one push-up than to a long workout. Fogg calls this idea the law of least effort, since people naturally choose the option requiring the least energy. ( ④ ) A student who wants to read more might leave a book open on the desk rather than setting a vague goal. By lowering the required effort, people reduce the ability barrier and make steady action far more achievable. ( ⑤ )

주어진 문장: In fields ranging from medicine to law, these tools now perform tasks that once required years of human training. As artificial intelligence grows more capable of performing tasks once considered exclusively human, many people wonder which skills will remain valuable in the future. ( ① ) AI can now analyze data, generate text, and even diagnose certain medical conditions with impressive accuracy. ( ② ) However, most researchers argue that AI still struggles with tasks requiring genuine empathy, ethical judgment, and creative problem-solving in unfamiliar situations. ( ③ ) A machine can recommend a treatment plan based on statistics, for instance, but it cannot comfort a frightened patient the way a compassionate nurse can. ( ④ ) Similarly, AI can generate countless design variations, yet it lacks the lived experience that allows humans to judge which idea truly resonates with people. ( ⑤ ) For this reason, educators increasingly emphasize skills such as collaboration, critical thinking, and emotional intelligence.

주어진 문장: This influence is so strong that many companies actively encourage customers to leave feedback after each purchase. Before making a purchase, most online shoppers now read reviews written by previous customers rather than relying solely on advertisements. ( ① ) These reviews, posted by people who have no financial connection to the seller, often seem more trustworthy than promotional claims. ( ② ) Research shows that products with a large number of positive reviews sell significantly more than those with few or no reviews at all. ( ③ ) However, fake reviews written by paid writers or even automated programs have become a serious problem, undermining consumer trust. ( ④ ) Platforms that fail to detect these fraudulent posts risk losing credibility with their users. ( ⑤ ) Ultimately, the power of online reviews depends entirely on their perceived honesty.