영어 모의고사 (자동 편성)

Before making a purchase, most online shoppers now read reviews ①written by previous customers rather than relying solely on advertisements. These reviews, posted by people who have no financial connection to the seller, often ②seem more trustworthy than promotional claims. Research shows that products with a large number of positive reviews ③sell significantly more than those with few or no reviews at all. However, fake reviews written by paid writers or even automated programs ④has become a serious problem, undermining consumer trust. To address this issue, several review platforms have begun ⑤using artificial intelligence to identify suspicious patterns.

Melatonin is a hormone ① produced by a small gland deep within the brain, and its release follows a remarkably predictable daily pattern. Levels stay low throughout the bright hours of the day, ② begin rising in the evening as darkness falls, peak in the middle of the night, and then decline again as morning approaches. This rhythm is controlled primarily by light: specialized cells in the eye detect brightness and send signals that either permit or ③ suppress melatonin production, which is why exposure to bright screens late at night can delay its release and make falling asleep more difficult. Unlike some hormones that directly cause the body to perform a task, melatonin does not force sleep to occur; instead, it signals to the rest of the body that night has arrived, ④ preparing various systems to shift into a lower-energy state. Because of this signaling role, taking melatonin supplements at the wrong time can shift a person's internal clock in the opposite direction from what was ⑤ intending.

Researchers who ① study teenagers have found a strong link between how well students sleep and how well they perform in school. Students who sleep fewer than seven hours a night tend to score lower on tests of memory and attention than those who ② sleep eight or nine hours, even when the two groups study for the same number of hours. One explanation is that sleep plays an active role in learning: during certain stages of sleep, the brain replays and strengthens information ③ encountered during the day, converting fragile short-term memories into more durable long-term ones. When sleep is cut short, this consolidation process is interrupted before it can finish, so material that seemed well understood the night before often ④ feel unfamiliar the next morning. For this reason, some schools have begun rethinking early start times, reasoning that an extra hour of sleep might do more for test scores than an extra hour of studying ever ⑤ could.

Time-management researchers frequently mention a principle known as Parkinson's Law, which states that work ①expands to fill the time available for its completion. According to this idea, a task that could be finished in one hour will often stretch to fill an entire afternoon if that much time is scheduled for it. Students who set ②vague deadlines frequently experience this effect, spending extra hours refining a report that was already ③complete. Employees given a full week for a simple project may also delay meaningful progress until the final days, even though the actual work requires far ④more effort. This pattern happens partly because people unconsciously adjust their pace to match perceived urgency. Setting shorter, more specific deadlines can ⑤counter this tendency, forcing tasks to fit within a tighter and more realistic window.

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. Consumers are becoming more ①careless, checking whether reviews are sponsored before making a purchase. In the end, influencer marketing works best when it ②stays ③grounded in ④authenticity rather than mere ⑤popularity.

The subscription economy refers to a business model in which consumers pay a recurring fee to access goods or services rather than owning them outright. This model has expanded rapidly beyond entertainment platforms into areas such as clothing, food, and even transportation. One major reason for this growth is ___________, since subscribers no longer need to make repeated purchasing decisions once they sign up. Another reason is that companies benefit from predictable revenue, which allows them to plan production and marketing more efficiently than with one-time sales. However, some critics argue that subscriptions encourage people to pay for services they barely use, quietly draining their monthly budgets.

Secondhand trading platforms, once considered a niche market for used goods, have grown into a mainstream part of consumer culture. Rising prices for new products, combined with growing awareness of environmental waste, have encouraged many shoppers to consider used items before purchasing something brand new. These platforms allow individuals to sell clothing, electronics, and furniture directly to other consumers, cutting out traditional retail markups entirely. However, buying secondhand carries certain risks, since items cannot always be inspected closely before purchase, and some sellers misrepresent the condition of their products. To address this problem, many platforms now offer buyer protection programs and detailed rating systems for sellers. As trust in these systems continues to grow, ___________.

VO2 max, defined as the maximum volume of oxygen a person's body can consume and use during intense exercise, is widely regarded as one of the best single indicators of cardiorespiratory fitness. (A) Elite endurance athletes typically post VO2 max values far higher than those of untrained individuals, reflecting hearts that pump larger volumes of blood and muscles that extract oxygen with remarkable efficiency. (B) While genetics accounts for a substantial portion of an individual's potential VO2 max, consistent aerobic training can still raise the measurement considerably over months of dedicated effort. (C) It is worth noting, however, that a high VO2 max does not guarantee success in competition, since other factors such as pacing strategy and mental resilience also play a decisive role.

Because the airway narrows gradually rather than closing all at once, the severity of each episode can vary widely. Sleep apnea is a disorder in which breathing repeatedly stops and restarts during sleep, often because the muscles at the back of the throat relax too much and block the airway. ( ① ) Each pause can last from a few seconds to over a minute, and it may occur dozens of times in a single night without the sleeper ever waking up fully. ( ② ) Because these interruptions rarely produce a clear memory the next morning, many people remain unaware that anything is wrong, even as chronic fatigue, headaches, and irritability build up over months. ( ③ ) Doctors therefore rely less on a patient's own account of the night and more on objective measurements, such as overnight oxygen levels and airflow patterns recorded in a sleep laboratory. ( ④ ) Left untreated, the disorder has been linked to serious long-term risks, including high blood pressure and heart disease, which makes an accurate diagnosis far more urgent than its subtle nighttime symptoms might suggest. ( ⑤ )

In other words, what looks like a lack of discipline may actually be a biological mismatch. Across many countries, high schools begin classes early in the morning, often before eight o'clock. ( ① ) This schedule assumes that teenagers can simply go to bed earlier to compensate, but biology tells a different story. ( ② ) During adolescence, the body's internal clock shifts later, delaying the release of melatonin until well after ten at night. ( ③ ) As a result, most teenagers are not physiologically ready to fall asleep until much later than younger children or adults are, and when early start times force them to wake before their bodies have completed a full sleep cycle, the mismatch accumulates into a chronic sleep debt that affects concentration and mood throughout the school day. ( ④ ) Researchers who study this mismatch argue that the underlying problem is not laziness or poor discipline among students, but a scheduling system built around adult rhythms rather than adolescent ones. ( ⑤ ) Some school districts that delayed their start times by thirty minutes reported improvements in attendance.