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 ①that governs when we feel alert and when we feel drowsy. This clock is regulated primarily by a tiny cluster of neurons in the brain ②that responds to light entering through the eyes. When morning sunlight strikes the retina, the cluster signals the body ③to 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 ④promotes 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 ⑤been associated with digestive problems and reduced concentration, suggesting that timing matters as much as total sleep hours.

Behavioral economists use the term temporal discounting to describe how people ①undervalue future rewards simply because those rewards are not immediate. This tendency explains why a student might choose to watch videos tonight rather than study for an exam that remains several weeks away, even though studying offers a ②smaller long-term benefit. A distant reward, no matter how valuable, feels psychologically smaller than a small reward available right now. This bias contributes to procrastination, since future consequences rarely feel ③urgent enough to motivate immediate action. To counter this tendency, students should ④convert distant goals into smaller, near-term milestones that feel more emotionally real. Setting weekly checkpoints rather than a final deadline can make future benefits feel ⑤closer and more concrete.

Jiho had always assumed he would join a large corporation after graduation, just as his parents expected. During his final year of university, however, he joined a small student team building an app that connected local farmers directly with restaurants. What started as a class project gradually turned into something more ①serious, as several restaurants began placing regular orders through their prototype. Jiho and his teammates decided to ②abandon their idea and instead spend a year developing it further, despite warnings from relatives who considered the plan too risky. They worked from a cramped apartment, surviving on ③limited savings while learning skills ranging from coding to negotiating with suppliers. After nearly failing twice, the team secured a small investment that allowed them to hire their first ④employee. Looking back, Jiho believes that the uncertainty of startup life taught him far more about problem-solving than any traditional job could have ⑤offered.

In the days leading up to an endurance event, many athletes deliberately ①increase their carbohydrate intake while reducing training volume, a practice known as carbohydrate loading. The strategy is designed to ②maximize the amount of glycogen, the storage form of carbohydrate, packed into muscle tissue before competition begins. Sports nutritionists caution, however, that the timing and composition of meals matter as much as the total quantity of carbohydrate consumed, since eating ③familiar foods immediately before competition can cause digestive discomfort. Athletes are therefore advised to ④practice their nutrition strategy during training rather than experimenting with it for the first time on race day. Beyond carbohydrates, adequate protein and micronutrient intake throughout the training cycle remains ⑤essential, since fueling strategy is only one part of a much larger nutritional picture.

When Mina was a freshman, she often spent her allowance within a few days. Her older cousin told her about the marshmallow experiment, a famous study in which children could eat one marshmallow ①immediately or wait for two. Researchers found that children who waited ②longer showed better academic performance and self-control years later. This ability to ③resist an immediate reward in favor of a larger future one is known as delayed gratification. Inspired by the study, Mina began saving half of her allowance each week instead of spending it all on snacks. At first, resisting small purchases felt surprisingly ④easy, especially when her friends were eating out. After three months, however, she had ⑤saved enough to buy a bicycle she had wanted for over a year.

Before making a purchase, most online shoppers now read reviews written by previous customers rather than relying solely on advertisements. These reviews, posted by people who have no financial connection to the seller, often seem more trustworthy than promotional claims. Research shows that products with a large number of positive reviews sell significantly more than those with few or no reviews at all. However, fake reviews written by paid writers or even automated programs have become a serious problem, undermining consumer trust. Platforms that fail to detect these fraudulent posts risk losing credibility with their users, who expect authentic opinions when making decisions. To address this issue, several review platforms have begun using artificial intelligence to identify suspicious patterns. Ultimately, the power of online reviews ___________.

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 ___________.

Sleep debt refers to the cumulative gap between the amount of sleep a person needs and the amount they actually get. Unlike a financial debt, however, this deficit cannot simply be repaid with a single long weekend of rest. When someone loses two hours of sleep every night for a week, the body does not treat the shortage as fourteen separate small losses; instead, it accumulates the deficit, and _______________. Researchers have found that even modest, chronic sleep restriction gradually impairs reaction time and decision-making, often without the affected person noticing the decline. This is because subjective feelings of tiredness tend to plateau after a few days, even as objective performance keeps deteriorating. Consequently, people frequently underestimate how much sleep debt they are carrying until a demanding task suddenly exposes the accumulated cost.

Across many countries, high schools begin classes early in the morning, often before eight o'clock. (A) 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. (B) This schedule assumes that teenagers can simply go to bed earlier to compensate, but biology tells a different story, because the body's internal clock shifts later during adolescence, delaying the release of melatonin until well after ten at night. (C) As a result, most teenagers are not physiologically ready to fall asleep until much later than adults, and when early start times force them to wake before completing a full sleep cycle, the mismatch accumulates into a chronic sleep debt.

3D printing has found practical applications across a surprisingly wide range of fields. (A) In medicine, for example, hospitals now create prosthetic limbs that are precisely tailored to each patient's body. (B) The automotive industry has also adopted the technology, using it to manufacture lightweight parts that improve fuel efficiency. (C) Even small businesses have gained access to manufacturing capabilities that were once available only to large corporations with significant capital.