영어 모의고사 (자동 편성)

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

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.

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 ①trustworthy than promotional claims. Research shows that products with a large number of positive reviews sell significantly ②more 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, ③undermining consumer trust. Platforms that fail to detect these fraudulent posts risk ④gaining credibility with their users, who expect authentic opinions when making decisions. Ultimately, the power of online reviews depends entirely on their perceived ⑤honesty.

Every day, email providers quietly block billions of unwanted messages before they ever reach a user's inbox. The filter examines each incoming message for suspicious patterns, including certain keywords, unusual sender addresses, and formatting tricks. What makes the system effective is that it keeps learning after launch: whenever a user marks a message as spam, that action becomes new training data, sharpening the filter's future decisions. This creates a constant back-and-forth, since spammers study which messages get blocked and then adjust their wording to slip through again. As a result, _______________.

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. (A) However, researchers caution strongly against interpreting these findings as evidence that athletic greatness is simply inherited. (B) 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. (C) 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.

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.

The rise of autonomous vehicles has created both excitement and anxiety within the transportation industry. (A) In particular, long-distance trucking jobs are expected to shrink significantly as autonomous trucks become more common on highways. (B) At the same time, entirely new positions are emerging, such as remote operators who monitor fleets of self-driving vehicles from control centers. (C) On one hand, many professional drivers fear that automation will eliminate the jobs they currently depend on.

Some welcome the tool as a quick way to sketch ideas before refining them by hand. 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. ( ① ) The software has studied thousands of existing songs, learning which chord progressions and rhythms tend to sound pleasant together, and it recombines these patterns into something new rather than copying any single source directly. ( ② ) For independent creators who cannot afford a composer or expensive licensing fees, this has been a genuine breakthrough. ( ③ ) Professional musicians, however, remain divided. ( ④ ) Others worry that a flood of AI-generated background music could quietly push human composers out of smaller, lower-budget projects, the very jobs many musicians once relied on to build a career. ( ⑤ )

주어진 문장: Even a short break from checking their phones can trigger a nagging sense of unease. Many teenagers check their social media accounts dozens of times a day, worried that they might miss something important happening among their friends. ( ① ) This anxiety, known as FOMO, or the fear of missing out, arises when people believe that others are enjoying experiences from which they themselves are excluded. ( ② ) For example, a student scrolling through photos of a party she was not invited to may suddenly feel a wave of loneliness and regret, even though the event has already ended. ( ③ ) Constantly refreshing feeds to avoid missing such updates, however, makes it difficult to concentrate on schoolwork or conversations happening in the present moment. ( ④ ) Moreover, this endless comparison with curated highlights of other people's lives tends to deepen feelings of anxiety rather than relieve them. ( ⑤ ) Therefore, students should learn to limit their social media use and focus more attention on the relationships and activities directly in front of them.

A request as ordinary as asking for tomorrow's weather, for instance, triggers a surprisingly long chain of computation behind the scenes. Smart speakers have quietly become a fixture in many households, responding to spoken requests for weather updates, music, or kitchen timers. ( ① ) Behind this simple exchange lies a complex process: the device converts sound waves into text, interprets the meaning using language models, and then generates a spoken reply, all within a second or two. ( ② ) Because these assistants improve by learning from millions of interactions, they gradually become better at recognizing regional accents and casual phrasing that once confused them. ( ③ ) Still, the technology remains far from perfect. ( ④ ) Background noise, overlapping voices, or an unusual sentence structure can cause the assistant to misunderstand a simple request, sometimes with amusing results. ( ⑤ ) Engineers continue to refine these systems, but many admit that truly natural conversation remains one of the hardest goals in the entire field of artificial intelligence.