Full Academic Reading Test

Reading Passage 1

AFor most of history, the height of buildings was strictly limited. Building higher meant thicker walls at the bottom to bear the weight, until the walls became so massive that they swallowed the ground floor. In the late nineteenth century, a combination of new materials and inventions suddenly removed that limit, and the tall building – the skyscraper – was born.

BThe key structural change was the steel frame. Instead of the walls carrying the weight of the building, engineers built a rigid skeleton of steel columns and beams. This frame carried the loads, and the outer walls became a thin “curtain” that merely kept out the weather. Freed from their old job of holding the building up, walls could now be made largely of glass, and buildings could rise far higher than stone had ever allowed.

CHeight, however, was useless without a way to reach it. Few people would willingly climb ten flights of stairs, let alone fifty. The invention that made tall buildings practical was the safety elevator. In 1853 Elisha Otis demonstrated a device that would not fall even if its cable was cut, and reliable passenger elevators soon followed. Without them, the upper floors of a tall building would have been almost worthless.

DThe first true skyscrapers rose in Chicago. After a great fire destroyed much of the city in 1871, architects there were free to experiment, and land in the business district was expensive enough to make building upward worthwhile. The Home Insurance Building, completed in 1885 and supported by a metal frame, is often called the first skyscraper, though it was modest by later standards.

EBuilding tall created problems that architects had never faced. Tall buildings sway in high winds, so their frames had to be braced to keep them stiff. Deep foundations were needed to stop them sinking into soft ground. Fire safety, water supply and the sheer weight of thousands of occupants all demanded new engineering. Each increase in height brought a fresh set of difficulties to solve.

FSkyscrapers also reshaped the cities around them. By packing many floors onto a small piece of land, they allowed great numbers of people to work in a compact centre, which encouraged the growth of dense business districts. Critics complained that clusters of towers blocked sunlight and funnelled cold winds through the streets below, and some cities passed laws forcing the upper floors to be “stepped back” so that light could still reach the ground.

GToday the skyscraper has spread far beyond its American birthplace, and the tallest now stand in the cities of Asia and the Middle East. Modern towers rely on lightweight materials, high-speed elevators and computer modelling that the first builders could not have imagined. Yet the basic idea has not changed: a strong inner frame doing the work that heavy walls once did.

Reading Passage 2

AOn a dark night, the sea sometimes glows. A breaking wave lights up in electric blue, or a ship’s wake glitters with cold fire. This living light is called bioluminescence – light produced by living organisms through a chemical reaction inside their bodies. Unlike the light of a bulb, it gives off almost no heat, which is why it is often described as “cold light”.

BThe chemistry behind the glow is remarkably similar across very different creatures. In most cases a molecule called luciferin reacts with oxygen, helped by a substance called luciferase, and the energy released escapes as light rather than heat. Because so little energy is wasted, bioluminescence is one of the most efficient ways of making light known to science – far more efficient than any electric lamp.

CBioluminescence is surprisingly common, but it is not spread evenly through nature. It is rare on land, where fireflies and certain fungi are among the few examples. In the ocean, however, it is everywhere: the majority of animals living in the deep sea can produce their own light. In a world that sunlight never reaches, the ability to make light brings clear advantages.

DAnimals use their light in many different ways. Some, like the anglerfish, dangle a glowing lure to draw prey towards their jaws. Others use light to find or attract a mate, flashing in patterns that only their own species recognises. Among fireflies, each species flashes its own rhythm – a code that lets males and females of the same kind identify one another in the dark.

ELight can also be a defence. When attacked, some squid release a cloud of glowing liquid instead of dark ink, dazzling a predator while they escape. Others use a trick known as counter-illumination: they glow faintly on their undersides so that, seen from below against the dim light of the surface, their outline disappears and they become almost invisible to hunters lurking beneath.

FScientists have found ways to put bioluminescence to work. The genes that produce light can be inserted into other cells, making them glow whenever a particular process is active. Researchers use this “reporter” light to watch how diseases spread, how genes switch on and off, and whether new drugs are working. A phenomenon that first appeared as a curiosity of the sea has become a valuable everyday tool in the laboratory.

Reading Passage 3

AOf the roughly seven thousand languages spoken in the world today, a large share are in danger of disappearing. Linguists estimate that somewhere in the world a language dies every few weeks, as its last fluent speakers grow old and pass away. By the end of this century, many experts fear, half or more of today’s languages may be gone.

BLanguages fall silent for many reasons. Sometimes speakers are pressured to abandon their mother tongue in favour of a more powerful national or global language that offers work and education. Sometimes children simply stop learning the language of their grandparents because it seems to carry no advantage. Rarely is a language lost through the sudden death of its community; far more often it fades gradually, one generation choosing not to pass it on to the next.

CThe loss of a language is not only the loss of words. Each language carries a unique way of seeing the world – knowledge of local plants and animals, stories, songs and history that may exist in no other form. When a language disappears, this store of understanding, built up over countless generations, can vanish with it, leaving humanity poorer in ways that are hard to measure.

DAround the world, communities are fighting back. Some record their elders speaking, creating archives of stories and vocabulary before it is too late. Others set up “language nests”, where young children spend their days with fluent older speakers and absorb the language naturally, as they would at home. Such programmes have helped several languages that were close to extinction begin to recover.

ETechnology has become a surprising ally. Mobile-phone apps now teach threatened languages to learners who have no one nearby to practise with, and social media let scattered speakers stay in contact and use their language every day. Dictionaries and lessons that once existed only on paper, if at all, can now reach anyone with an internet connection.

FReviving a language, though, is rarely easy. It takes years of effort, money and, above all, a community that genuinely wants its language to survive. Success also depends on younger people choosing to speak it – not out of duty, but because it is woven into daily life. Where these conditions are met, even a language with very few speakers can be brought back from the edge.