영어 모의고사 (자동 편성)

Exercise does far more than strengthen muscles and the heart; it also produces measurable changes within the brain itself. During sustained physical activity, the body ①releases a protein called brain-derived neurotrophic factor, which supports the growth of new neurons and ②strengthens connections between existing ones, particularly in regions associated with memory and learning. Studies comparing physically active students to sedentary peers have repeatedly found that the active group ③performing better on tests of attention and problem-solving, even when the exercise session ends well before the test begins. Researchers believe that exercise increases blood flow to the brain, ④delivering oxygen and nutrients more efficiently, while also reducing levels of stress hormones that can interfere with clear thinking. These findings have encouraged some schools ⑤to schedule exercise before demanding academic classes.

Instead of typing keywords into a search bar, a growing number of people now simply upload a photo and let an algorithm ①figure out what it contains. This process, known as reverse image search, compares the visual patterns in a picture against a massive database, ②identifying everything from a landmark in the background to the exact model of a pair of sneakers. Shoppers use it to find where an item seen on the street can ③be purchased, while students use it to identify plants, insects, or historical artworks in seconds. The system works by breaking an image down into countless small features, then ④matches that pattern against millions of stored examples. It is not flawless, however; a blurry photo, an unusual camera angle, or an object partly hidden behind another can easily ⑤confuse the algorithm.

Researchers who ①study 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 ②sleep 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 ③encountered 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 ④feel 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 ⑤could.

Until last spring, Minji ①rarely thought twice about tossing a paper cup into the trash after finishing her coffee. Environmental issues seemed ②distant, something scientists and politicians should handle rather than an ordinary student like her. That changed when her class was assigned a documentary about plastic waste drifting through the ocean, footage she initially expected to find boring. Instead, watching seabirds mistake plastic fragments for food left her strangely ③comforted, and she found herself thinking about the assignment long after class ended. The next morning, almost without deciding to, she slipped her old tumbler into her backpack instead of buying a disposable cup on the way to school. It felt like a small, ④meaningless gesture at first. However, as weeks passed, she realized that consistently choosing the tumbler, declining a plastic straw, and reusing a shopping bag were quietly ⑤adding up. Small choices, she discovered, become meaningful once repeated.

Feed an AI music program a mood, a tempo, and a rough genre, and within seconds it can generate a complete instrumental track, ready to be dropped under a video or used as background music for a small business. The software has studied thousands of existing songs, learning which chord progressions and rhythms tend to sound ①pleasant together, and it ②recombines these patterns into something new rather than copying any single source directly. For independent creators who cannot afford a composer or expensive licensing fees, this has been a genuine ③breakthrough. Professional musicians, however, remain divided. Some welcome the tool as a quick way to sketch ideas before refining them by hand, while others ④celebrate that a flood of AI-generated background music could quietly push human composers out of smaller, lower-budget projects. ⑤the very jobs many musicians once relied on to build a career.

Adaptive learning apps promise something no traditional classroom can easily offer: a lesson plan that adjusts itself to each individual student in real time. As a student answers practice questions, the app tracks which concepts are mastered and which remain shaky, then quietly reshuffles the next set of problems to target the weaker areas. However, critics caution that _______________. There is also a subtler concern: students who grow used to instant, algorithm-generated feedback may struggle later with the slower, more ambiguous kind of feedback that real-world tasks and mentors typically provide.

Scientists have identified certain gene variants that appear more frequently among elite endurance athletes than among the general population, along with a separate set that seems to favor explosive, power-based sports such as sprinting. One frequently studied variant, for instance, influences the proportion of slow-twitch versus fast-twitch muscle fibers a person naturally develops, a ratio that shapes whether a body leans toward endurance or explosive power. However, researchers caution strongly against interpreting these findings as evidence that athletic greatness is simply inherited, since _______________. Genetics may set a rough ceiling on an individual's ultimate potential, but where any particular athlete lands within that range depends overwhelmingly on training quality, nutrition, coaching, and sheer determination.

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. (A) This gentle activity keeps blood circulating through tired muscles, which appears to help clear metabolic byproducts more efficiently than complete stillness does. (B) Some athletes worry that any movement at all will interfere with the repair process, but research suggests that truly light activity does not meaningfully slow healing. (C) 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.

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. (A) Because glycogen serves as the primary fuel source during prolonged, intense exercise, entering an event with fuller stores can delay the point of exhaustion that runners often call hitting the wall. (B) Sports nutritionists caution, however, that the timing and composition of meals matter as much as the total quantity of carbohydrate consumed. (C) The strategy is designed to maximize the amount of glycogen, the storage form of carbohydrate, packed into muscle tissue before competition begins.

This shift in emphasis reflects a growing understanding of what actually happens inside the body while an athlete is asleep. Coaches have traditionally focused athlete preparation on training volume and nutrition, but a growing body of research suggests that sleep deserves equal attention. ( ① ) During deep sleep, the body releases growth hormone, a substance essential for repairing muscle tissue damaged during intense training, while the brain consolidates motor skills practiced earlier that day into more stable, efficient patterns. ( ② ) Athletes who sleep fewer than seven hours a night have been shown to suffer more injuries, slower reaction times, and reduced accuracy compared to well-rested peers performing the identical drills. ( ③ ) Frequent travel across time zones compounds this challenge considerably, since jet lag can disrupt an athlete's natural sleep-wake cycle for several days after a long flight, sometimes right before an important competition. ( ④ ) In response, many professional teams now employ sleep specialists who design travel schedules, control bedroom lighting and temperature, and even adjust competition start times when possible. ( ⑤ )