영어 모의고사 (자동 편성)

Across the world, teenagers are chronically short on sleep, often getting two or three hours less than the eight to ten hours experts recommend for their age. Part of the problem lies in biology: as puberty begins, the body's internal clock naturally shifts later, ① making it difficult for teenagers to fall asleep before eleven at night. Yet school start times rarely adjust to this shift, ② forcing students to wake before their bodies are ready. The consequences extend well beyond simple tiredness. Chronic sleep loss during adolescence has been linked to impaired concentration, weakened memory, and a higher risk of anxiety and depression. It can also disrupt the hormones ③ that regulating appetite, contributing to unhealthy weight gain over time. Some school districts have experimented with ④ delaying start times by even thirty minutes, and early results suggest that students who gain that extra rest show improved grades, better mood, and fewer tardy arrivals. Despite this evidence, changing entrenched school schedules ⑤ remains a slow and contentious process.

Caffeine is the most widely consumed stimulant in the world, ① prizing for its ability to 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 ② makes us feel increasingly sleepy the longer we stay awake. By occupying the receptors that adenosine would normally bind to, caffeine tricks the brain into ③ 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 ④ consumed in the late afternoon may still be interfering with the ability to fall asleep at midnight. Even when people do not consciously notice difficulty falling asleep, caffeine has been shown ⑤ to reduce the amount of deep, restorative sleep obtained later in the night.

After an especially demanding training session, the instinct to collapse onto a couch and remain motionless is understandable, yet exercise physiologists increasingly recommend the ① opposite approach. 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. This gentle activity keeps blood circulating through tired muscles, which appears to help ② clear metabolic byproducts that accumulate during hard exercise more efficiently than complete stillness does. Some athletes worry that any movement at all will interfere with the repair process, but research suggests that truly light activity ③ accelerates healing considerably and may even reduce the perceived soreness that follows a hard session. The key distinction lies entirely in ④ 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 ⑤ mechanisms.

Influencer marketing has become one of the most powerful tools that companies use to reach young consumers. Unlike traditional advertisements, which often feel distant and impersonal, posts created by influencers seem more like advice from a trusted friend. This sense of closeness, built through years of sharing daily life online, makes followers more willing to trust product recommendations than ordinary commercials. For example, a skincare brand promoted by a popular lifestyle influencer can sell out within hours simply because her audience believes her opinions are honest. However, this trust can be exploited when influencers promote products they have never actually tried. As a result, several countries now require influencers to clearly disclose paid partnerships before posting sponsored content. Consumers are becoming more cautious, checking whether reviews are sponsored before making a purchase. In the end, influencer marketing ___________.

Wearable devices 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 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. Independent studies comparing wearable data with polysomnography, the gold-standard method used in clinical sleep labs, have found that _______________. 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. 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.

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 most closely associated with physical restoration. REM sleep, by contrast, brings rapid eye movements, near-total muscle paralysis, and brain activity that closely resembles wakefulness. Most vivid dreaming occurs during this stage, and researchers believe _______________. A healthy night typically cycles through both stages four or five times, with non-REM dominating the early hours and REM periods lengthening toward morning. Disrupting either stage, through frequent awakenings or alcohol use, can leave a person feeling unrested even after a full night in bed.

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. This clock is regulated primarily by a tiny cluster of neurons in the brain that responds to light entering through the eyes. When morning sunlight strikes the retina, the cluster signals the body to suppress sleep hormones and raise body temperature, preparing us for activity. As evening approaches and light fades, _______________. 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 been associated with digestive problems and reduced concentration, suggesting that timing matters as much as total sleep hours.

Skipping a proper warm-up before intense exercise might seem like a harmless way to save a few minutes, but the practice carries real physiological costs, since a cold muscle is stiffer and less elastic than a warm one. Gradually raising body temperature through light activity increases blood flow to the muscles and speeds up nerve signals between the brain and the muscle fibers. A proper warm-up also raises heart rate gradually, easing the cardiovascular system into strenuous work. As a result, _______________. For this reason, coaches treat warm-up routines not as optional preparation but as an essential part of training itself.

A short nap taken in the early afternoon, often called a power nap, can noticeably sharpen attention and mood without leaving a person groggy afterward. (A) If a nap extends much beyond that window, the sleeper risks waking during deep sleep, which produces a foggy, disoriented feeling known as sleep inertia that can persist for thirty minutes or more. (B) The key lies in timing: naps limited to roughly twenty minutes allow the brain to pass through the lightest stages of sleep while avoiding the deeper stages associated with slow-wave activity. (C) Laboratory studies comparing napping and non-napping groups have repeatedly shown that a brief nap improves reaction time and short-term memory almost as effectively as a full night of extra rest. Interestingly, the benefit appears strongest when the nap occurs several hours after waking, since this is when the body's natural dip in alertness makes rest most effective. For this reason, many workplaces now designate quiet rooms where employees can recharge briefly during the day.

주어진 문장: She walked into the interview room feeling confident, certain that her past online activity had nothing to do with her qualifications. When Minji was in ninth grade, she posted a joking comment mocking a classmate's photo, never imagining anyone would remember it later. ( ① ) Three years passed, and she nearly forgot the comment existed, buried among hundreds of old posts. ( ② ) Last spring, she applied to join her school's student council, hoping her leadership experience would impress the selection committee. ( ③ ) During the interview, however, one teacher mentioned having seen an old, unkind comment under Minji's name while reviewing applicants' profiles. ( ④ ) Startled, Minji realized that everything she had ever posted online had quietly accumulated into what is called a digital footprint, a lasting trail of personal data left behind by online activity. ( ⑤ ) Although she deleted the comment immediately, the damage to her reputation had already been done. She understood that digital footprints rarely disappear completely, even when the original posts are removed, because screenshots and memories often outlast the content itself.