PTE Listening Fill in the Blanks Practice

Over the last ten years, urban beekeeping has grown quickly. Many rooftops, school gardens and community allotments now honeybee colonies. Supporters say the hives help pollinate the flowers and vegetables that grow nearby. However, city bees face challenges that rural bees do not. Their food sources are often and scattered, because gardens are small and parks are far apart. Beekeepers also have to the hive regularly to check for disease. Researchers at several universities are currently whether city honey contains fewer pesticides than honey from farmland. Their early results are promising, but they need data before drawing firm conclusions.

Tea was not always an everyday drink in Britain. In the eighteenth century, it was an expensive that only wealthy households could afford. Merchants brought it from China, and the East India Company later large plantations in Assam to reduce its dependence on Chinese supply. Today, the region produces a large share of the world's black tea. Workers there have long-standing concerns about low wages and working conditions, and campaigners continue to highlight them. Some producers now certification schemes to show buyers that their practices meet agreed standards. Historians note that the story of tea is with colonial trade, and its legacy is still visible in the way we drink it.

Sleep plays a central role in how the brain stores new information. During the night, the brain the experiences of the day and decides which ones to keep. Researchers have found that people who sleep after learning a list of words tend to more of them the next morning than people who stay awake. The effect appears to depend on deep sleep, which is the stage when the brain activity between different regions. Students who an all-nighter before an exam often find that their recall is worse, not better. The simplest advice from sleep scientists is to a regular bedtime and to avoid screens in the hour before sleep.

Kelp forests grow in cool, shallow coastal water and form some of the most productive habitats in the ocean. Kelp is a large brown that can grow more than thirty centimetres in a single day. Fish, crabs and many other animals shelter among its long . Sea urchins feed on kelp, and when too many urchins , they can strip an entire forest bare. Sea otters help prevent this because they eat urchins and keep their numbers . Where otters have returned, kelp forests have often begun to . Scientists now monitor these coastlines carefully, since healthy kelp also absorbs carbon dioxide and the shore from strong waves.

When archaeologists dig a site, they record every of soil they remove. The idea is simple. In most places, the oldest material lies at the and the newest at the top, because each generation builds on what was left before. A coin or a piece of pottery found in a layer helps to everything around it. Of course, the ground is not always so tidy. Animals burrow, farmers plough, and floods can the earlier deposits. That is why careful notes and matter as much as the finds themselves. Once a layer has been removed, it can never be put back, so a dig is a form of destruction, and the written record is all that remains of it.

Many cities are rethinking how they use street space. For most of the twentieth century, planners designed roads mainly for cars, which led to wide and long distances between homes and shops. More recently, some planners have the idea of the fifteen-minute neighbourhood, where daily needs can be reached on foot or by bicycle. Supporters argue that this reduces traffic and improves local air . It can also strengthen small , because residents spend more of their money close to home. Critics warn that the idea is difficult to apply in areas that are already and that housing near popular centres may become more . For this reason, many planners combine it with affordable housing and reliable public transport.

Every year, a tree adds a new ring of wood beneath its bark. In a wet year the ring is wide, and in a dry year it is . Scientists who study these patterns, a field known as dendrochronology, can rings from living trees with those in old timber from buildings. By overlapping many samples, they have built a continuous stretching back thousands of years in some regions. Archaeologists use it to find the exact year a roof beam was . The method works best in places with distinct , where growth slows in winter. In tropical forests, rings are often faint or absent, so the technique is far less there.

In a market economy, prices carry information. When a fails and wheat becomes , its price usually rises. That rise tells buyers to use less and encourages farmers elsewhere to grow more. No single person plans the outcome, yet millions of separate decisions are . However, markets do not always work smoothly. If sellers hold a , they can raise prices without losing customers. Some costs, such as the damage caused by factory smoke, may also never appear in the price, and economists describe these as . Governments therefore some markets, although they must be careful not to remove the very signals that make markets work well.

The word monsoon describes a seasonal change in wind direction, not just heavy rain. In summer, land heats faster than the , so warm air over the continent and pulls moist air in from the sea. This brings the rainy season to South Asia between June and . In winter the pattern reverses and the winds blow from the land towards the sea, so the weather is mostly . Farmers depend on the timing of these rains to their crops. If the rains arrive late, the harvest can suffer. Forecasters therefore watch the of the ocean surface closely, because it influences how strong the season will be.

Students often try to learn a topic by studying it for many hours in one night. Psychologists call this , and it can produce good results in a test the next morning. However, the information is usually within a few days. A better method is spaced practice, which means dividing study time into short sessions over several . Each time you return to the material, you must make an effort to it from memory, and this effort strengthens the memory. Testing yourself with simple questions is more effective than reading your notes again and again. Research on this idea goes back to the century, when a German scientist named Hermann Ebbinghaus measured how quickly people lists of meaningless syllables.

Cities are often several degrees warmer than the surrounding countryside, an effect known as the urban heat . Dark roads and roofs sunlight during the day and release it slowly at night. Buildings also block the wind, and there are fewer plants to the air through evaporation. Planners can reduce the effect in several ways. Planting trees provides shade, while pale-coloured roofs more sunlight. Some cities are also creating narrow green that allow breezes to pass through. During a heatwave, these measures can make a real difference to the of elderly residents.

Solar panels convert sunlight directly into , but they produce power only when the sun is shining. This creates a problem for electricity networks, because demand is often highest in the evening, after the sun has set. One solution is to store energy during the day. Large batteries are now beside many solar farms, and they release electricity when it is needed. Another approach is pumped hydropower, in which water is pumped up to a high reservoir and later allowed to back down through turbines. Network operators can also encourage households to use appliances at different times, a practice sometimes called demand . Together, these methods help to supply and demand.

Growing the same crop in the same field year after year gradually the soil. Different plants take different nutrients, so farmers have long their crops. Legumes such as peas and beans are especially valuable because bacteria in their roots convert nitrogen from the air into a form that other plants can . A traditional four-year rotation might include wheat, turnips, barley and clover. Besides restoring fertility, rotation also interrupts the life cycles of that prefer a particular crop. As a result, farmers can often their use of fertiliser and pesticide. The practice is simple in principle, but it requires careful over several seasons.

Before the fifteenth century, books in Europe were copied by hand, usually by , and a single volume could take months to finish. Around 1450, a named Johannes Gutenberg developed a printing system in the German city of Mainz. His key innovation was metal type, in which each letter was cast separately and could be for the next page. Combined with a press adapted from those used for wine and olives, this method allowed printers to produce many copies quickly. Within fifty years, printing workshops had appeared across Europe, and the price of books sharply. Historians generally agree that printed material helped ideas to travel faster and contributed to growing literacy.

Fermentation is one of the oldest methods of preparing and food. Microorganisms such as yeast and bacteria break down sugars and produce acids, gases or alcohol. In bread making, yeast releases carbon dioxide, which makes the dough . In yoghurt, bacteria turn the sugar in milk into lactic acid, which gives a flavour and thickens the texture. The acid also makes it difficult for harmful microbes to . Vegetables preserved by fermentation include sauerkraut in Germany and kimchi in Korea, though the differ. Because fermentation depends on living organisms, temperature must be carefully .

In 1854, a severe outbreak of struck the Soho district of London. At that time, many doctors believed the disease was spread through bad air. A named John Snow doubted this idea, so he mapped the homes of the people who had died. He noticed that the deaths were around a single water pump on Broad Street. After local officials removed the pump handle, the number of new cases declined. Snow's work is often regarded as an early example of , the study of how disease spreads through populations. It also showed that clean drinking water and proper are essential to public health. Later, scientists identified the responsible.

Education ministries often debate how long children should stay in education. In many countries the school-leaving age has been over the past century. Supporters argue that extra years of study improve prospects and narrow gaps between rich and poor families. Critics respond that students who have lost interest may simply , and that money might be better spent on early childhood programmes. Most researchers agree that quality matters as much as . A longer school day with poor teaching does little good. Policymakers therefore tend to pair any extension with investment in teacher and clear ways to measure progress.

All languages change over time. English speakers today would find it almost impossible to understand a text written in Old English more than a thousand years ago. Some changes affect , as when certain vowels gradually . Others affect : new words appear for new , and old words may take on different meanings. Contact between communities also matters. When people who speak different languages trade with one another, they often words from each other. Linguists do not regard change as a sign of decline. They see it as a natural that shows a language is still used by living speakers.

Universities are increasingly rethinking how they students. Traditional end-of-year examinations reward the ability to recall information under pressure, but they reveal little about how well a student can sustain a long . Continuous assessment spreads marks across the term through essays, presentations and group work. It can lower anxiety and encourage steady . However, it raises its own difficulties. Staff must mark more work, and there is a greater risk of when assignments are completed at home. Some departments have therefore adopted a model that combines short supervised tests with larger coursework tasks. Supporters say students value the .

Coral reefs cover less than one percent of the ocean floor, yet they support about a quarter of all marine . Reef-building corals are tiny animals that live in partnership with microscopic . The algae live inside the coral's tissue, where they use sunlight to make food and give the coral its colour. When the water becomes unusually warm, the coral can the algae, and its skeleton turns white. This is known as . A bleached coral is not dead, but it is weakened and may starve if conditions do not improve. Researchers are also studying which corals heat best, hoping to damaged reefs with more resilient varieties.

A light-year is a unit of , not time. It is the distance that light in a vacuum in one year, which is roughly nine and a half trillion kilometres. The nearest star beyond our Sun, Proxima Centauri, is a little over four light-years . This means the light we see from it tonight left the star more than four years . Looking at distant objects is therefore a form of looking into the . Some of the most remote galaxies visible to modern are seen as they were billions of years ago, long before the Earth formed.

Every choice involves giving something up. Economists use the term opportunity cost for the value of the next best that you do not choose. Suppose you have a free afternoon. You could work for four hours and earn some money, or you could spend the time with friends. If you choose to meet friends, the opportunity cost is the you did not earn. Businesses face the same kind of decision. A company with a limited cannot spend it on everything, so managers must possible projects. Governments also face this problem, since money used for a new road cannot be used for a . Understanding opportunity cost helps people make more carefully.

Since the 1990s, astronomers have confirmed thousands of planets orbiting other stars. Most are too faint and too close to their star to be photographed directly, so scientists rely on indirect . In the transit method, a telescope monitors a star's . If a planet passes in front of the star, the light dips slightly, and the dip repeats at intervals. From the size of the dip, researchers can estimate how large the planet is. A second approach measures the tiny that a planet's gravity causes in its star's motion. Combining both techniques reveals a planet's mass and size, and therefore its . That helps scientists judge whether it is rocky or .

Working memory is the mental we use to hold information for a short time while we think. When you remember a telephone number just long enough to dial it, you are using working memory. Its is limited. In the 1950s, the psychologist George Miller suggested that people can hold about seven items at once, give or take two, although later researchers proposed that the true number may be . One way to overcome this limit is , in which separate items are combined into larger meaningful . For example, the letters of a familiar word are easier to remember than the same letters in order. Experts in chess seem to use this strategy, because they recognise whole of pieces rather than single squares.

Medieval builders wanted cathedrals with tall walls and large windows, but stone is heavy, and thick walls limit the amount of . The solution was the flying buttress, an external arch that carries the of the roof away from the wall and down to a heavy support outside. Because the wall no longer carries the whole load, it can be and filled with stained glass. The pointed arch also helped, since it directs weight more steeply downward than a one. Together, these features allowed interiors that feel and tall. The builders had no mathematical theory of forces, so much of their knowledge came from .

The electric telegraph changed communication in the nineteenth century. Before it existed, messages could travel only as fast as a horse, a ship or a train. The telegraph sent signals along metal as short and long of electric current, which were later translated into letters. Samuel Morse and his colleagues developed a for this purpose, and the first public line in the United States opened in 1844. Within a few decades, cables stretched across continents, and in 1866 a cable was successfully laid beneath the Ocean. Newspapers could now report distant events within hours. Businesses also benefited, since could check prices in other cities and make deals quickly. In effect, the telegraph the speed of information from the speed of transport.

Engineers are now designing tall buildings with frames. The material is called cross-laminated timber, in which layers of wood are glued at right angles to increase . Wood is lighter than concrete, so the foundations can be smaller. Trees also store carbon as they grow, which means a timber building can some of it away for decades. Fire safety is a common worry, but thick wood on the outside and protects the inner layers, so it burns slowly and predictably. Cost remains an obstacle, and builders need specialised . Still, several cities have approved timber towers of more than ten .

For many years, people believed that growing up with two languages children and delayed their development. Modern research has largely this view. Bilingual children may mix words from both languages in a single sentence, but this behaviour, called code-switching, follows regular rules and is not a sign of confusion. Some studies suggest that managing two languages gives the brain regular practice in selecting relevant information and ignoring . However, the size of this benefit remains debated, and not every study has the earliest findings. Educators therefore encourage families to continue using their home language, since it supports , communication with relatives and later at school.

Before the 1950s, loading a cargo ship was slow and . Dockworkers handled sacks and crates one by one, and a vessel could spend days in port. The standard shipping container changed this. Because every box has the same dimensions, cranes can lift it from a ship onto a train or a without unpacking it. This is called intermodal . Port time fell sharply, and the cost of moving goods across oceans dropped. However, the system depends on careful . A delay at one terminal can create a that affects ships weeks later. Empty containers also pile up in some regions, and returning them is a persistent .

Tidal energy comes from the regular rise and fall of the sea, which is caused mainly by the pull of the Moon. Unlike wind and sunshine, tides are highly , so engineers can calculate years in advance how much power a tidal station will generate. One design uses a , a low dam built across a river mouth. As the tide flows in and out, water passes through in the dam. Another design places turbines directly in fast-flowing channels. Tidal power has drawbacks. Barrages can disturb fish and the of birds, and equipment must survive salt water and powerful . Costs are also high, which is why tidal power currently supplies only a small of the world's electricity.

The last mile is the final stage of a delivery, from a local depot to the customer's . Although it is a short distance, it often makes up a big part of the total . Vans must stop many times, and the driver may find that nobody is at . Companies are testing several solutions. Some place parcels in secure lockers at stations or shops so that customers can them at a convenient time. Others use cargo bikes in crowded city centres, where they can be quicker than vans and cause less . Better route planning software also helps drivers avoid journeys.

Washing your hands with soap is one of the simplest ways to prevent . Many travel from person to person on our hands, especially after we cough, use the toilet or handle food. Public health experts recommend washing for at least seconds. The soap does not need to be . Soap works by lifting dirt and germs from the skin so that running water can wash them away. In the nineteenth century, a Hungarian doctor named Ignaz Semmelweis showed that when doctors cleaned their hands before delivering babies, far fewer mothers suffered from . His ideas were at first, but they later became standard practice in hospitals around the world.

For many years, scientists believed the adult brain was fixed. We now know that it can change its connections in response to experience, a property called . When you practise a skill, such as playing the piano, the links between the relevant neurons become . Brain of professional musicians show differences in regions that control fine finger movement. Plasticity is especially in childhood, which is why young learners often pick up languages so easily. Yet it continues throughout life. After a stroke, for example, undamaged areas can sometimes take over lost with the help of therapy. Researchers stress that change requires and attention, not simply the passage of time.

Neurons do not touch one another. Between them is a tiny gap called a synapse. The signal is within the cell but chemical between cells. When it reaches the end of a neuron, it releases chemical messengers known as . These molecules cross the gap and attach to on the next cell, which may then fire its own signal. Dopamine, for instance, is involved in and movement. Some medicines work by how these chemicals are released or cleared away. Because each neuron may connect with thousands of others, the resulting network is extraordinarily .