영어 모의고사 (자동 편성)

Wearable devices ① that track sleep have become enormously popular, promising a detailed breakdown of light, deep, and REM sleep each night. These gadgets typically rely on movement sensors and heart rate monitors ② to estimate sleep stages, since directly measuring brain activity would require equipment found only in a sleep laboratory. Independent studies ③ compares 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 ④ underestimate the amount of time spent in REM sleep, and the margin of error can vary widely between brands. Despite these limitations, many users have come ⑤ 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.

The gig economy, in which people take on short-term or freelance jobs, ①has grown rapidly over the past decade. Digital platforms now connect customers directly with drivers, designers, and writers, ②allowing workers to choose when and how much they work. Businesses, meanwhile, can hire help only when they ③actually need it. For many young people entering the job market, gig work provides valuable flexibility ④that traditional employment rarely allows. However, gig workers often lack benefits such as health insurance, which full-time employees typical ⑤receive.

Caffeine is the most widely consumed stimulant in the world, prized for its ability to ① sharpen focus and fight off fatigue within minutes of consumption. It works by blocking adenosine, a chemical that gradually builds up in the brain throughout the day and makes us feel ② decreasingly sleepy the longer we stay awake. By occupying the receptors that adenosine would normally bind to, caffeine tricks the brain into feeling alert even when the body has accumulated significant sleep pressure. The effects, however, last far longer than most people realize. Because caffeine can remain active in the bloodstream for five to six hours, a cup of coffee consumed in the late afternoon may still be ③ interfering with the ability to fall asleep at midnight. Even when people do not consciously notice difficulty falling asleep, caffeine has been shown to ④ reduce the amount of deep, restorative sleep obtained later in the night. For this reason, many sleep specialists advise ⑤ avoiding caffeine after early afternoon.

In the days leading up to an endurance event, many athletes deliberately increase their carbohydrate intake while reducing training volume, a practice known as carbohydrate loading. The strategy is designed to maximize the amount of glycogen, the storage form of carbohydrate, packed into muscle tissue before competition begins. Because glycogen serves as the primary fuel source during prolonged, intense exercise, _______________. Sports nutritionists caution, however, that the timing and composition of meals matter as much as the total quantity of carbohydrate consumed, since eating unfamiliar foods immediately before competition can cause digestive discomfort.

Many people believe that building a new habit requires strong willpower or motivation. However, psychologist BJ Fogg argues that habits form more easily when a behavior itself becomes simple to perform. His theory, called the Fogg Behavior Model, states that ___________. When motivation is low, the task must be made extremely easy, or it will not happen at all. 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. 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.

For centuries, dreams have fascinated scientists and philosophers alike, yet no single theory fully explains why the sleeping brain generates such vivid and often bizarre experiences. (A) Another theory proposes that dreams serve a more practical function, allowing the brain to rehearse responses to threats without any real danger, a kind of nightly simulation that may have offered early humans a survival advantage. (B) Still other researchers argue that dreaming is simply a byproduct of the brain organizing memories rather than serving any independent purpose, and because these theories rest on indirect evidence, none has been conclusively proven, leading many scientists to suspect that dreaming may serve several functions simultaneously. (C) One prominent idea suggests that dreaming helps the brain process emotional experiences, replaying difficult events in a safe, low-stakes environment so that their emotional intensity gradually fades.

Every cell in the human body follows an internal timer known as the circadian rhythm, a roughly twenty-four-hour cycle that governs when we feel alert and when we feel drowsy. (A) This clock is regulated primarily by a tiny cluster of neurons in the brain that responds to light entering through the eyes, signaling the body to suppress sleep hormones each morning. (B) As evening approaches and light fades, however, the same mechanism triggers the release of melatonin, a hormone that promotes drowsiness. (C) Because this rhythm evolved around the natural cycle of day and night, modern habits such as artificial light exposure or night shifts can push it out of sync, which has been linked to digestive problems and reduced concentration.

Social media algorithms are designed to keep users engaged by showing them content they are likely to enjoy. (A) As a result, users are gradually exposed to a narrower and narrower range of perspectives over time. (B) This pattern, known as an echo chamber, can eventually lead to greater political polarization within a society. (C) To achieve this goal, the algorithms recommend posts and articles similar to what a user has already liked or shared.

Temporal discounting offers a useful lens for understanding why long-term goals so often lose out to short-term pleasures. (A) Consequently, replacing distant, abstract goals with smaller, immediate milestones can make future rewards feel psychologically closer and more motivating. (B) Research shows that people consistently prefer a smaller reward available today over a considerably larger reward promised weeks later. (C) This preference persists even when the delayed reward is clearly the more rational choice, revealing how strongly immediacy influences decision-making.

The key distinction lies entirely in intensity: active recovery is not a second workout in disguise but a deliberately gentle session designed to support, rather than compete with, the body's underlying repair mechanisms. After an especially demanding training session, the instinct to collapse onto a couch and remain motionless is understandable, yet exercise physiologists increasingly recommend the opposite approach. ( ① ) Active recovery involves performing low-intensity movement, such as a light jog, an easy swim, or a gentle bike ride, on days following intense exertion rather than resting completely. ( ② ) This gentle activity keeps blood circulating through tired muscles, which appears to help clear metabolic byproducts that accumulate during hard exercise more efficiently than complete stillness does. ( ③ ) Some athletes worry that any movement at all will interfere with the repair process. ( ④ ) Research suggests, however, that truly light activity, kept well below the intensity of the original workout, does not meaningfully slow healing and may even reduce the perceived soreness that follows a hard session. ( ⑤ )