영어 모의고사 (자동 편성)

Anyone who has ridden a bicycle after a decade away from one has likely ① experiencing muscle memory firsthand: the body seems to recall a complex skill almost instantly, even when conscious memory of the exact movements has faded. Contrary to what the name suggests, muscles themselves do not actually store memories; the phenomenon originates in the brain and nervous system, where repeated practice gradually ② shifts control of a well-learned movement from regions associated with conscious thought to areas that operate largely automatically. This shift explains why a skilled athlete can ③ execute a complicated sequence of movements without consciously thinking through each individual step, freeing mental attention for strategy and decision-making instead. Interestingly, research also suggests that these neural pathways can remain partially intact even after long periods without practice, which is why relearning a skill is typically much ④ faster than learning it for the very first time. Coaches often exploit this principle by ⑤ ensuring that fundamental techniques are practiced correctly from the very beginning.

For decades, athletes were taught to stretch a muscle and hold the position before any competition, ① believing that this practice alone would prevent injury. Recent research, however, has complicated that assumption considerably. Static stretching, in which a muscle ② is held at its longest length for an extended period, can actually reduce the muscle's ability to generate explosive force immediately afterward. Dynamic stretching, which involves controlled, repeated movement through a joint's full range of motion, ③ appears to prepare muscles for activity without this temporary weakening effect. As a result, many coaches now recommend ④ to save static stretching for after a workout, when it may help restore muscle length and reduce soreness, while ⑤ reserving dynamic movements for the warm-up period before intense effort begins.

When the body fights off an infection, the immune system relies heavily on adequate sleep to function ① effectively. During deep sleep, the body produces and releases cytokines, proteins that help ② regulate immune responses and coordinate the fight against harmful invaders. People who consistently sleep fewer than six hours a night show measurably ③ weaker antibody responses after vaccination compared with those who sleep seven or eight hours. Chronic sleep deprivation also appears to ④ reduce low-grade inflammation throughout the body, a state that has been linked to a higher risk of heart disease. Rather than being a passive state, sleep functions as an active period during which the immune system repairs itself and ⑤ prepares for future threats.

Modern sports wearables, from wrist-worn fitness trackers to smart insoles embedded in running shoes, continuously collect data that would once have required a laboratory to measure. Heart rate, sleep quality, running cadence, and even subtle changes in gait can now be ① monitored during ordinary daily activity rather than only in a controlled clinical setting. Coaches use this constant stream of information to detect early warning signs of overtraining, sometimes noticing a decline in performance ② after the athlete consciously feels tired. However, the flood of data has created a new challenge: distinguishing a meaningful pattern from ordinary daily fluctuation requires expertise that many amateur athletes simply ③ do not have. Some researchers worry that casual users may misinterpret a single unusual reading as a serious problem, leading to ④ needless anxiety rather than useful insight. For this reason, most experts recommend treating wearable data as a general trend to observe over time, not as a precise ⑤ diagnostic tool.

Across many countries, high schools begin classes early in the morning, often before eight o'clock. This schedule assumes that teenagers can simply go to bed earlier to compensate, but biology tells a different story. During adolescence, the body's internal clock shifts later, delaying the release of melatonin until well after ten at night. As a result, most teenagers are not physiologically ready to fall asleep until much later than younger children or adults. 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. Researchers who study this mismatch argue that _______________. Some school districts that delayed their start times by thirty minutes reported improvements in attendance, suggesting that the timing of the school day matters more than commonly assumed.

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.

During sleep, the brain does not simply rest; it actively reorganizes the day's experiences into lasting memories through a process called consolidation. (A) Sleep researchers have demonstrated this effect experimentally: participants who slept after learning a list of word pairs recalled more items the next day than participants who remained awake instead. Crucially, the benefit was not limited to simple recall; sleep also seemed to help participants extract general patterns from the material, suggesting that consolidation involves more than passive storage. (B) Newly formed memories are initially fragile and stored primarily in a brain region called the hippocampus, which has limited long-term capacity. (C) While a person sleeps, particularly during the deep stages of non-REM sleep, neural activity replays these fresh memory traces in rapid, compressed sequences, gradually transferring the information to the cortex for more durable, long-term storage. This replay strengthens the connections between neurons that encoded the original experience, making the memory more resistant to interference from unrelated events the following day.

Recovering from a serious sports injury involves far more than simply waiting for torn tissue to heal; it requires a carefully structured program that gradually reintroduces stress to the affected area. (A) Progressing too quickly at this stage is a common mistake, since tissue that appears healed on the surface may still be structurally fragile beneath it. (B) Skipping the final stage of sport-specific drills, even when an athlete feels fully recovered, dramatically increases the risk of re-injury, because general strength does not automatically translate into the coordination a sport demands. (C) Immediately after an injury, rest and gentle range-of-motion exercises give way to light resistance training as pain subsides, slowly rebuilding strength in muscles weakened by disuse.

Shoppers use it to find where an item seen on the street can be purchased, while students use it to identify plants, insects, or historical artworks in seconds. Instead of typing keywords into a search bar, a growing number of people now simply upload a photo and let an algorithm figure out what it contains. ( ① ) This process, known as reverse image search, compares the visual patterns in a picture against a massive database, identifying everything from a landmark in the background to the exact model of a pair of sneakers. ( ② ) The system works by breaking an image down into countless small features, such as edges, colors, and shapes, then matching that pattern against millions of stored examples. ( ③ ) It is not flawless, however. ( ④ ) A blurry photo, an unusual camera angle, or an object partly hidden behind another can easily confuse the algorithm, leading to search results that have nothing to do with the original picture at all. ( ⑤ )

For this reason, nutritionists generally advise spreading moderate portions of protein evenly across several meals throughout the day rather than saving it all for one large post-workout meal. After a strenuous workout, muscle fibers experience thousands of microscopic tears, and the body immediately begins a repair process that ultimately makes the muscle stronger than it was before. ( ① ) This repair depends heavily on amino acids, the building blocks that protein supplies, which is why sports scientists recommend consuming protein within a couple of hours after training. ( ② ) Waiting too long to eat can slow recovery, since a muscle's sensitivity to amino acids gradually declines once that window closes. ( ③ ) Many athletes assume that eating an enormous quantity of protein in a single sitting will speed up this process. ( ④ ) But the body can only use a limited amount at once; the rest is simply burned for energy or stored as fat. ( ⑤ )