영어 모의고사 (자동 편성)

Wearable devices ①that 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 ②to estimate sleep stages, since directly measuring brain activity would require equipment found only in a sleep laboratory. Independent studies ③compares 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 ④underestimate 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 ⑤to 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.

Every cell in the human body follows an internal timer known as the circadian rhythm, a roughly twenty-four-hour cycle that ①governs 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 ②suppress 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 that ③promotes 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 ④out of sync with the external environment. Such misalignment does not simply cause tiredness; it has also been associated with digestive problems and ⑤heightened concentration, suggesting that timing matters as much as total sleep hours.

Mira had lived in a coastal village since birth, watching the tide creep closer to her family's doorstep every year. When the sea finally swallowed the rice paddies that had fed her village for generations, her parents decided that staying was no longer possible. Together with many neighbors, they packed what little they could carry and moved inland, becoming what experts now call climate migrants, _______________. This term, rarely used a decade ago, has become increasingly common as extreme weather displaces communities worldwide. Mira missed her old house terribly, yet she slowly began to build a new life in the crowded city, learning to adapt just as her ancestors once had. International organizations, however, still struggle to agree on how to protect people like her, since climate migrants are not officially recognized as refugees under current law.

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 ___________.

When Mina graduated from college five years ago, she had never even heard the term "data scientist." Everything changed when a small tech startup, which was building an app to predict traffic patterns, hired her to analyze massive amounts of data. Mina quickly discovered that she loved turning raw numbers into insights that helped real people make better decisions. Within two years, ___________, as companies in every industry realized how valuable data could be. Today, Mina leads a team of ten analysts, mentoring young graduates who are drawn to a field that barely existed when she began her own career.

Many self-help books emphasize the cue-routine-reward loop as a tool for building better habits. (A) For example, athletes who want to build a stretching habit often rely on a specific cue, such as arriving at the gym, to trigger the same short routine every time. (B) Over time, this consistent pairing strengthens the neural pathway connecting the cue to the routine, making the behavior feel almost automatic. (C) According to this model, every habit consists of three connected parts: a cue that triggers behavior, a routine that follows, and a reward that reinforces it.

Many economists have studied how automation affects different sectors of the economy, and their research reveals a consistent pattern. (A) For example, manufacturing plants that adopted robotics saw production speed double within five years, while the number of routine assembly jobs fell sharply. (B) As a result, workers today are encouraged to develop skills that complement machines rather than compete with them, such as creativity and critical thinking. (C) At first, automation mainly affected repetitive manual tasks in manufacturing, but it has since spread into administrative and even creative fields.

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. (A) REM sleep, by contrast, brings rapid eye movements and brain activity resembling wakefulness, and is believed to help consolidate memories and process emotions. (B) A healthy night cycles through both stages several times, and disrupting either one can leave a person feeling unrested despite a full night in bed. (C) During non-REM sleep, particularly its deepest stage, the brain waves slow dramatically and the body focuses on physical repair.

Smartphones, tablets, and computer screens all emit a significant amount of blue light, a short-wavelength light that our eyes are especially sensitive to. (A) At night, however, the same wavelength can interfere with the body's natural preparation for sleep by suppressing the release of melatonin. (B) During the day, exposure to blue light from the sun helps keep us alert and mentally sharp, which is generally beneficial. (C) For this reason, some devices now offer a night mode that shifts the display toward warmer tones, though sleep researchers still recommend limiting screen use before bedtime.

This mismatch between internal time and local time is the true source of the problem, not the flight itself. Travelers who cross several time zones in a single flight often arrive feeling exhausted, foggy, and strangely out of sync with the local clock, a condition widely known as jet lag. ( ① ) The discomfort arises because the body's internal clock, which governs sleep, hunger, and alertness, continues to run on the schedule of the departure city even after landing. ( ② ) Realigning this internal clock to a new time zone is not instantaneous; researchers estimate that the body typically needs about one day to adjust for every time zone crossed. ( ③ ) Flying eastward tends to produce more severe symptoms than flying westward, because advancing the internal clock forward is generally harder for the body than delaying it. ( ④ ) Exposure to natural light at the right moments after arrival can help speed up the adjustment, since light is the strongest external cue the internal clock uses to reset itself. ( ⑤ ) Without such adjustments, travelers may continue to experience disrupted sleep and reduced concentration for several days after a long international flight.