Questões de Inglês — vocabulário, substituição de palavras e reescrita

Long-haul truck drivers are among the most exposed workers on any highway network, and fatigue remains one of their deadliest hazards. Studies of road crashes involving heavy vehicles suggest that drowsiness plays a role in a significant share of collisions, although the exact figure is hard to establish, since tired drivers who survive rarely admit to having dozed off.

The problem is rooted in the economics of freight. Many drivers are paid by the trip or by the kilometre rather than by the hour, which encourages them to cut rest stops short. Tight delivery windows set by shippers add further pressure. As a result, some drivers turn to stimulants to stay awake, a practice that may delay sleep but does not restore alertness.

Regulators have responded with rules limiting continuous driving time and requiring minimum rest periods. Electronic logging devices, which record when a vehicle is moving, have made these rules harder to dodge. However, enforcement depends on inspections, and secure parking areas where drivers can actually rest are still scarce along many routes.

Technology offers another line of defence. Some fleets now install in-cab cameras that track eye movements and sound an alarm when a driver's eyelids stay closed for too long. Supporters argue that such systems save lives; critics counter that constant monitoring erodes drivers' privacy and may shift responsibility from employers to individual workers.

A researcher who studies transport safety at a public university put it bluntly: no device can replace a good night's sleep. In her view, unless pay structures change, drivers will keep trading rest for income, and the roads will remain more dangerous than they need to be.

Long-haul truck drivers are among the most exposed workers on any highway network, and fatigue remains one of their deadliest hazards. Studies of road crashes involving heavy vehicles suggest that drowsiness plays a role in a significant share of collisions, although the exact figure is hard to establish, since tired drivers who survive rarely admit to having dozed off.

The problem is rooted in the economics of freight. Many drivers are paid by the trip or by the kilometre rather than by the hour, which encourages them to cut rest stops short. Tight delivery windows set by shippers add further pressure. As a result, some drivers turn to stimulants to stay awake, a practice that may delay sleep but does not restore alertness.

Regulators have responded with rules limiting continuous driving time and requiring minimum rest periods. Electronic logging devices, which record when a vehicle is moving, have made these rules harder to dodge. However, enforcement depends on inspections, and secure parking areas where drivers can actually rest are still scarce along many routes.

Technology offers another line of defence. Some fleets now install in-cab cameras that track eye movements and sound an alarm when a driver's eyelids stay closed for too long. Supporters argue that such systems save lives; critics counter that constant monitoring erodes drivers' privacy and may shift responsibility from employers to individual workers.

A researcher who studies transport safety at a public university put it bluntly: no device can replace a good night's sleep. In her view, unless pay structures change, drivers will keep trading rest for income, and the roads will remain more dangerous than they need to be.

Highways are not only the arteries of legitimate trade; they also serve as corridors for one of the world's most lucrative illegal markets. Wild animals captured in forests are frequently moved by road, hidden in car boots, buses and lorries, before reaching urban buyers or ports from which they are shipped abroad.

Parrots, songbirds, turtles and small primates are among the species most often seized. Traffickers typically pack them into plastic bottles, socks or cramped boxes to escape detection. Conservation groups estimate that most animals taken from the wild die before they reach their final destination, either from suffocation, dehydration or stress. This means that each animal sold represents several others that perished along the way.

Roadside inspections remain a key tool against the trade. Officers trained to recognise suspicious cargo, unusual noises or the smell of animal waste have intercepted shipments that would otherwise have gone unnoticed. Yet traffickers adapt quickly. When checkpoints become predictable, they switch routes, split loads among several vehicles or travel at night.

Seizure is only the first step, however. Rescued animals need veterinary care, and many cannot be released immediately because they are weak or have lost their natural fear of humans. Rehabilitation centres are often overcrowded and underfunded, which forces authorities to make difficult choices about where to send them.

Experts also point out that penalties for wildlife crime tend to be light compared with those for drug or arms trafficking, even though the same criminal networks are sometimes involved in all three. Stronger sentences, combined with intelligence sharing between police and environmental agencies, could make the business less attractive.

Highways are not only the arteries of legitimate trade; they also serve as corridors for one of the world's most lucrative illegal markets. Wild animals captured in forests are frequently moved by road, hidden in car boots, buses and lorries, before reaching urban buyers or ports from which they are shipped abroad.

Parrots, songbirds, turtles and small primates are among the species most often seized. Traffickers typically pack them into plastic bottles, socks or cramped boxes to escape detection. Conservation groups estimate that most animals taken from the wild die before they reach their final destination, either from suffocation, dehydration or stress. This means that each animal sold represents several others that perished along the way.

Roadside inspections remain a key tool against the trade. Officers trained to recognise suspicious cargo, unusual noises or the smell of animal waste have intercepted shipments that would otherwise have gone unnoticed. Yet traffickers adapt quickly. When checkpoints become predictable, they switch routes, split loads among several vehicles or travel at night.

Seizure is only the first step, however. Rescued animals need veterinary care, and many cannot be released immediately because they are weak or have lost their natural fear of humans. Rehabilitation centres are often overcrowded and underfunded, which forces authorities to make difficult choices about where to send them.

Experts also point out that penalties for wildlife crime tend to be light compared with those for drug or arms trafficking, even though the same criminal networks are sometimes involved in all three. Stronger sentences, combined with intelligence sharing between police and environmental agencies, could make the business less attractive.

Police forces in several countries have started to use live facial recognition, a technology that compares the faces of passers-by with images stored in watch lists. Cameras mounted on vans or poles scan crowds in real time, and an alert is sent to officers whenever the software finds a probable match.

Advocates say the system helps locate fugitives and missing persons far faster than traditional methods. In some trials, wanted suspects were arrested within minutes of walking past a camera. Moreover, the technology does not get tired or distracted, unlike human officers watching hours of footage.

Civil liberties groups, on the other hand, warn that mass scanning turns everyone into a potential suspect. They also raise concerns about accuracy. Earlier generations of algorithms were found to produce more false matches for women and people with darker skin, partly because they had been trained on unrepresentative data sets. Developers claim that recent versions have narrowed this gap, but independent audits are not always available to confirm it.

A false match is not merely a technical glitch. For the person wrongly stopped, it may mean being questioned in public, searched or even detained. Critics argue that the burden of proving innocence should never fall on someone simply because a machine flagged their face.

Some cities have banned the use of facial recognition by public agencies altogether, while others allow it under strict conditions, such as judicial authorisation, clear limits on how long images can be stored and regular reporting on results. Lawmakers in many places, however, have yet to set any specific rules, leaving decisions largely in the hands of police leaders.

Police forces in several countries have started to use live facial recognition, a technology that compares the faces of passers-by with images stored in watch lists. Cameras mounted on vans or poles scan crowds in real time, and an alert is sent to officers whenever the software finds a probable match.

Advocates say the system helps locate fugitives and missing persons far faster than traditional methods. In some trials, wanted suspects were arrested within minutes of walking past a camera. Moreover, the technology does not get tired or distracted, unlike human officers watching hours of footage.

Civil liberties groups, on the other hand, warn that mass scanning turns everyone into a potential suspect. They also raise concerns about accuracy. Earlier generations of algorithms were found to produce more false matches for women and people with darker skin, partly because they had been trained on unrepresentative data sets. Developers claim that recent versions have narrowed this gap, but independent audits are not always available to confirm it.

A false match is not merely a technical glitch. For the person wrongly stopped, it may mean being questioned in public, searched or even detained. Critics argue that the burden of proving innocence should never fall on someone simply because a machine flagged their face.

Some cities have banned the use of facial recognition by public agencies altogether, while others allow it under strict conditions, such as judicial authorisation, clear limits on how long images can be stored and regular reporting on results. Lawmakers in many places, however, have yet to set any specific rules, leaving decisions largely in the hands of police leaders.

Sales of electric cars have grown rapidly over the past decade, driven by falling battery prices, government incentives and growing concern about air pollution. Yet the expansion of charging infrastructure has not kept pace, particularly outside large cities.

For drivers who live in houses with a garage, charging is relatively simple: they plug in overnight and start the day with a full battery. Those who live in apartments or park on the street face a different reality. They depend on public chargers, which are often concentrated in wealthy neighbourhoods and along major motorways, leaving rural areas and smaller towns underserved.

Long journeys pose a further challenge. Fast chargers can restore most of a battery's range in under an hour, but they are expensive to install and require robust connections to the electricity grid. In regions where the grid is already under strain, a cluster of fast chargers at a highway service station may demand upgrades costing millions.

Heavy vehicles add another layer of complexity. Electric trucks need much larger batteries than cars, which reduces the weight of cargo they can carry and lengthens charging times. For this reason, some analysts believe that hydrogen or overhead power lines may prove more practical for long-distance freight, although neither option has yet been adopted on a large scale.

Governments are therefore under pressure to plan networks rather than leave the market to decide where chargers go. Without coordination, experts warn, the transition to cleaner transport could deepen existing inequalities, as those with the means to charge at home reap the benefits while others are left behind.

Sales of electric cars have grown rapidly over the past decade, driven by falling battery prices, government incentives and growing concern about air pollution. Yet the expansion of charging infrastructure has not kept pace, particularly outside large cities.

For drivers who live in houses with a garage, charging is relatively simple: they plug in overnight and start the day with a full battery. Those who live in apartments or park on the street face a different reality. They depend on public chargers, which are often concentrated in wealthy neighbourhoods and along major motorways, leaving rural areas and smaller towns underserved.

Long journeys pose a further challenge. Fast chargers can restore most of a battery's range in under an hour, but they are expensive to install and require robust connections to the electricity grid. In regions where the grid is already under strain, a cluster of fast chargers at a highway service station may demand upgrades costing millions.

Heavy vehicles add another layer of complexity. Electric trucks need much larger batteries than cars, which reduces the weight of cargo they can carry and lengthens charging times. For this reason, some analysts believe that hydrogen or overhead power lines may prove more practical for long-distance freight, although neither option has yet been adopted on a large scale.

Governments are therefore under pressure to plan networks rather than leave the market to decide where chargers go. Without coordination, experts warn, the transition to cleaner transport could deepen existing inequalities, as those with the means to charge at home reap the benefits while others are left behind.

A message arrives from an unknown number claiming to be a relative who has just changed phones. Within minutes, the sender asks for an urgent transfer to pay a bill. Variations of this scam have spread across messaging apps, and police in many countries report that it has become one of the most common forms of fraud.

The scheme works not because the technology is sophisticated but because it exploits trust and haste. Criminals often collect photos and personal details from social media profiles to make the impersonation convincing. Some even use artificial intelligence to clone a relative's voice from short audio clips posted online, which makes a follow-up call sound disturbingly genuine.

Instant payment systems, which allow money to move between accounts in seconds, have made life easier for consumers, but they have also made stolen funds harder to recover. By the time a victim realises what has happened, the money has frequently been split among several accounts held by so-called "money mules", people who lend or sell access to their bank accounts.

Banks have introduced measures such as transaction limits at night and delays for transfers to new recipients. Investigators say, however, that prevention ultimately depends on users. Their advice is simple: hang up, contact the relative through a known number and never transfer money under pressure.

Older people are frequently targeted, but younger users are far from immune. Surveys indicate that people who consider themselves digitally skilled may in fact be more likely to fall for a scam, precisely because they are confident that it could never happen to them.

A message arrives from an unknown number claiming to be a relative who has just changed phones. Within minutes, the sender asks for an urgent transfer to pay a bill. Variations of this scam have spread across messaging apps, and police in many countries report that it has become one of the most common forms of fraud.

The scheme works not because the technology is sophisticated but because it exploits trust and haste. Criminals often collect photos and personal details from social media profiles to make the impersonation convincing. Some even use artificial intelligence to clone a relative's voice from short audio clips posted online, which makes a follow-up call sound disturbingly genuine.

Instant payment systems, which allow money to move between accounts in seconds, have made life easier for consumers, but they have also made stolen funds harder to recover. By the time a victim realises what has happened, the money has frequently been split among several accounts held by so-called "money mules", people who lend or sell access to their bank accounts.

Banks have introduced measures such as transaction limits at night and delays for transfers to new recipients. Investigators say, however, that prevention ultimately depends on users. Their advice is simple: hang up, contact the relative through a known number and never transfer money under pressure.

Older people are frequently targeted, but younger users are far from immune. Surveys indicate that people who consider themselves digitally skilled may in fact be more likely to fall for a scam, precisely because they are confident that it could never happen to them.

Roads were designed for the climate of the past. Engineers calculated drainage capacity, pavement materials and bridge foundations based on decades of historical weather records, assuming that the future would look much like what had come before. That assumption is increasingly being called into question.

Heavier downpours are overwhelming culverts and drainage channels, causing flash floods that wash away sections of road and undermine embankments. In mountainous areas, saturated slopes give way, burying highways under tonnes of mud and rock. At the other extreme, prolonged heatwaves soften asphalt, leading to ruts and cracks, while wildfires force the closure of entire corridors for days.

The costs go well beyond repairs. When a key highway is cut off, communities may lose access to hospitals, food deliveries and fuel, and businesses that depend on just-in-time supplies can grind to a halt. Emergency services, meanwhile, struggle to reach those most in need.

Transport agencies are beginning to adapt. Some are raising road levels in flood-prone areas, enlarging drainage structures and using heat-resistant binders in asphalt. Others are installing sensors on slopes and bridges to detect movement before a collapse. Such measures are expensive, but studies commissioned by public bodies often conclude that every unit of currency invested in resilience saves several in future damage.

Even so, adaptation alone will not be enough if global emissions keep rising. Climate scientists stress that infrastructure built today will still be in use decades from now, when conditions may be considerably harsher than anything recorded so far.

Roads were designed for the climate of the past. Engineers calculated drainage capacity, pavement materials and bridge foundations based on decades of historical weather records, assuming that the future would look much like what had come before. That assumption is increasingly being called into question.

Heavier downpours are overwhelming culverts and drainage channels, causing flash floods that wash away sections of road and undermine embankments. In mountainous areas, saturated slopes give way, burying highways under tonnes of mud and rock. At the other extreme, prolonged heatwaves soften asphalt, leading to ruts and cracks, while wildfires force the closure of entire corridors for days.

The costs go well beyond repairs. When a key highway is cut off, communities may lose access to hospitals, food deliveries and fuel, and businesses that depend on just-in-time supplies can grind to a halt. Emergency services, meanwhile, struggle to reach those most in need.

Transport agencies are beginning to adapt. Some are raising road levels in flood-prone areas, enlarging drainage structures and using heat-resistant binders in asphalt. Others are installing sensors on slopes and bridges to detect movement before a collapse. Such measures are expensive, but studies commissioned by public bodies often conclude that every unit of currency invested in resilience saves several in future damage.

Even so, adaptation alone will not be enough if global emissions keep rising. Climate scientists stress that infrastructure built today will still be in use decades from now, when conditions may be considerably harsher than anything recorded so far.

Police officers are routinely exposed to events that most people encounter rarely, if ever: fatal crashes, violent assaults, the deaths of children. Over the course of a career, these experiences can accumulate, and research consistently shows that officers face higher rates of post-traumatic stress, depression and substance abuse than the general population.

Despite this, many officers are reluctant to seek help. Police culture has traditionally prized toughness and self-control, and admitting to emotional difficulties may be seen as a sign of weakness. Some officers also fear that a mental health diagnosis could cost them their weapon, their assignment or even their job.

Shift work compounds the problem. Irregular hours disrupt sleep, strain family relationships and leave little time for exercise or rest. Furthermore, officers frequently move from one stressful call to the next without the chance to process what they have just witnessed.

A growing number of departments have begun to respond. Peer support programmes train volunteer officers to recognise warning signs in colleagues and to offer a confidential first conversation. Others have made periodic psychological check-ups mandatory for everyone, so that attending one no longer singles anyone out. Supervisors are also being taught to speak openly about their own struggles, which, according to mental health professionals, helps to break down stigma.

Such initiatives benefit not only the officers themselves. Exhausted and traumatised officers are more prone to errors of judgement, including the unnecessary use of force. Looking after their wellbeing, therefore, is also a matter of public safety.

Across many of the world's largest cities, public transport systems are struggling to win back passengers lost during the pandemic. Although ridership has recovered in some places, it remains well below pre-2020 levels in others, largely because remote work has reduced the number of daily commuters. As fare revenue falls, transit agencies face a difficult choice: raise ticket prices or cut services. Either option, however, tends to drive even more riders away.

Some city governments have chosen a different path. Instead of charging more, they have lowered fares or, in a few cases, eliminated them altogether. Supporters argue that free buses encourage people to leave their cars at home, which reduces congestion and air pollution. Critics, on the other hand, point out that cost is rarely the main reason people avoid public transport. According to several surveys, passengers care far more about frequency, reliability and safety than about the price of a ticket.

Experts suggest that the answer probably lies somewhere in between. "Cheaper fares may attract new users, but they will not stay if the bus never arrives on time," said a transport planner who has advised several municipal governments. She added that investment in dedicated bus lanes could make journeys faster at a relatively low cost.

Meanwhile, urban sprawl continues to make the problem worse. As families move to distant neighbourhoods in search of affordable housing, they often end up in areas poorly served by trains and buses. For them, owning a car is no longer a choice but a necessity. Unless housing and transport policies are planned together, cities may keep building roads that fill up as soon as they are opened.

Across many of the world's largest cities, public transport systems are struggling to win back passengers lost during the pandemic. Although ridership has recovered in some places, it remains well below pre-2020 levels in others, largely because remote work has reduced the number of daily commuters. As fare revenue falls, transit agencies face a difficult choice: raise ticket prices or cut services. Either option, however, tends to drive even more riders away.

Some city governments have chosen a different path. Instead of charging more, they have lowered fares or, in a few cases, eliminated them altogether. Supporters argue that free buses encourage people to leave their cars at home, which reduces congestion and air pollution. Critics, on the other hand, point out that cost is rarely the main reason people avoid public transport. According to several surveys, passengers care far more about frequency, reliability and safety than about the price of a ticket.

Experts suggest that the answer probably lies somewhere in between. "Cheaper fares may attract new users, but they will not stay if the bus never arrives on time," said a transport planner who has advised several municipal governments. She added that investment in dedicated bus lanes could make journeys faster at a relatively low cost.

Meanwhile, urban sprawl continues to make the problem worse. As families move to distant neighbourhoods in search of affordable housing, they often end up in areas poorly served by trains and buses. For them, owning a car is no longer a choice but a necessity. Unless housing and transport policies are planned together, cities may keep building roads that fill up as soon as they are opened.

In many developing countries, getting children into school is no longer the main challenge. Enrolment in primary education has grown steadily over the past three decades, and in several regions it is now close to universal. The real problem, education specialists say, begins a few years later, when a significant share of teenagers quietly leave the classroom before finishing secondary school.

The reasons behind this trend are varied. Poverty remains the most frequently cited factor, since many adolescents feel pressure to earn money to support their families. Yet economic hardship alone does not explain the whole picture. Studies conducted in different countries show that students who repeat a grade are far more likely to drop out, partly because they feel embarrassed to study alongside younger classmates. Early pregnancy, long distances between home and school, and a curriculum that seems disconnected from the job market also play a role.

Dropping out has consequences that go well beyond the individual. Young people who abandon their studies tend to earn lower wages throughout their lives and are more vulnerable to unemployment. Some research has also linked low schooling to higher rates of involvement in crime, although the authors of these studies warn that the relationship is complex and should not be read as simple cause and effect.

To tackle the problem, governments have tried several strategies. Cash transfer programmes, which pay families on condition that their children attend classes, have produced encouraging results in some places. Other initiatives focus on identifying students at risk early on, by monitoring absences and grades. Whatever the approach, specialists agree on one point: once a teenager has left school, bringing him or her back is much harder than preventing the departure in the first place.

In many developing countries, getting children into school is no longer the main challenge. Enrolment in primary education has grown steadily over the past three decades, and in several regions it is now close to universal. The real problem, education specialists say, begins a few years later, when a significant share of teenagers quietly leave the classroom before finishing secondary school.

The reasons behind this trend are varied. Poverty remains the most frequently cited factor, since many adolescents feel pressure to earn money to support their families. Yet economic hardship alone does not explain the whole picture. Studies conducted in different countries show that students who repeat a grade are far more likely to drop out, partly because they feel embarrassed to study alongside younger classmates. Early pregnancy, long distances between home and school, and a curriculum that seems disconnected from the job market also play a role.

Dropping out has consequences that go well beyond the individual. Young people who abandon their studies tend to earn lower wages throughout their lives and are more vulnerable to unemployment. Some research has also linked low schooling to higher rates of involvement in crime, although the authors of these studies warn that the relationship is complex and should not be read as simple cause and effect.

To tackle the problem, governments have tried several strategies. Cash transfer programmes, which pay families on condition that their children attend classes, have produced encouraging results in some places. Other initiatives focus on identifying students at risk early on, by monitoring absences and grades. Whatever the approach, specialists agree on one point: once a teenager has left school, bringing him or her back is much harder than preventing the departure in the first place.

False information has always existed, but social media has changed the speed and scale at which it spreads. A misleading post can reach millions of people within hours, long before journalists or fact-checkers have had the chance to verify it. Researchers have found that false stories tend to travel faster than accurate ones, possibly because they are often more surprising and emotionally charged.

The consequences can be serious. During health emergencies, rumours about fake cures have led people to take dangerous substances. In election periods, fabricated stories about candidates or about the voting system itself may undermine public trust in democratic institutions. Even when a false claim is later corrected, the correction rarely reaches as many people as the original message did.

Governments around the world have responded in different ways. Some have passed laws requiring platforms to remove harmful content quickly, while others have preferred to invest in public awareness campaigns. Both approaches have drawn criticism. Strict regulation, opponents argue, could be used to silence legitimate dissent, whereas education campaigns take years to produce visible effects.

Technology companies, for their part, say they are doing more than ever to address the issue. They have hired content moderators, labelled suspicious posts and reduced the visibility of accounts that repeatedly share false material. Nevertheless, critics claim that the business model of these platforms, which rewards content that generates engagement, works against such efforts.

Many specialists believe that the most effective long-term defence is media literacy. Teaching people, especially young people, to check sources, compare information and recognise manipulation techniques may not stop every rumour, but it can make societies less vulnerable to them.

False information has always existed, but social media has changed the speed and scale at which it spreads. A misleading post can reach millions of people within hours, long before journalists or fact-checkers have had the chance to verify it. Researchers have found that false stories tend to travel faster than accurate ones, possibly because they are often more surprising and emotionally charged.

The consequences can be serious. During health emergencies, rumours about fake cures have led people to take dangerous substances. In election periods, fabricated stories about candidates or about the voting system itself may undermine public trust in democratic institutions. Even when a false claim is later corrected, the correction rarely reaches as many people as the original message did.

Governments around the world have responded in different ways. Some have passed laws requiring platforms to remove harmful content quickly, while others have preferred to invest in public awareness campaigns. Both approaches have drawn criticism. Strict regulation, opponents argue, could be used to silence legitimate dissent, whereas education campaigns take years to produce visible effects.

Technology companies, for their part, say they are doing more than ever to address the issue. They have hired content moderators, labelled suspicious posts and reduced the visibility of accounts that repeatedly share false material. Nevertheless, critics claim that the business model of these platforms, which rewards content that generates engagement, works against such efforts.

Many specialists believe that the most effective long-term defence is media literacy. Teaching people, especially young people, to check sources, compare information and recognise manipulation techniques may not stop every rumour, but it can make societies less vulnerable to them.

The number of people forced to flee their homes has reached record levels in recent years. Wars, persecution and, increasingly, the effects of extreme weather have pushed millions to cross borders in search of safety. Contrary to a widespread perception, however, most refugees do not travel to wealthy nations. The majority are hosted by low- and middle-income countries that share a border with the place they left.

International law makes a clear distinction between refugees and economic migrants. A refugee is someone who cannot return to his or her country because of a well-founded fear of persecution, and who is therefore entitled to protection. Under the principle of non-refoulement, states must not send such a person back to a place where his or her life or freedom would be threatened. Economic migrants, by contrast, move mainly to improve their living conditions and do not enjoy the same legal protection.

In practice, the line between the two groups is not always easy to draw. Many people leave for a mixture of reasons, and their journeys often expose them to smugglers, traffickers and other forms of exploitation. Border officials, therefore, face the difficult task of identifying who needs international protection while also controlling irregular entry.

Integration is another challenge. Studies show that refugees who are allowed to work and learn the local language soon after arriving tend to contribute more to the host economy and depend less on public assistance. Long waiting periods, on the other hand, can leave them idle for years, which harms both their mental health and their future job prospects. For this reason, several organisations have called for faster asylum procedures and earlier access to the labour market.

The number of people forced to flee their homes has reached record levels in recent years. Wars, persecution and, increasingly, the effects of extreme weather have pushed millions to cross borders in search of safety. Contrary to a widespread perception, however, most refugees do not travel to wealthy nations. The majority are hosted by low- and middle-income countries that share a border with the place they left.

International law makes a clear distinction between refugees and economic migrants. A refugee is someone who cannot return to his or her country because of a well-founded fear of persecution, and who is therefore entitled to protection. Under the principle of non-refoulement, states must not send such a person back to a place where his or her life or freedom would be threatened. Economic migrants, by contrast, move mainly to improve their living conditions and do not enjoy the same legal protection.

In practice, the line between the two groups is not always easy to draw. Many people leave for a mixture of reasons, and their journeys often expose them to smugglers, traffickers and other forms of exploitation. Border officials, therefore, face the difficult task of identifying who needs international protection while also controlling irregular entry.

Integration is another challenge. Studies show that refugees who are allowed to work and learn the local language soon after arriving tend to contribute more to the host economy and depend less on public assistance. Long waiting periods, on the other hand, can leave them idle for years, which harms both their mental health and their future job prospects. For this reason, several organisations have called for faster asylum procedures and earlier access to the labour market.

Renewable energy is no longer a niche industry. Over the last decade, the cost of electricity generated by solar panels and wind turbines has fallen so sharply that, in many countries, building a new solar farm is now cheaper than building a new coal or gas power plant. As a result, investment in clean energy has surpassed investment in fossil fuels for the first time in several major economies.

Despite this progress, the transition is far from complete. Fossil fuels still account for the largest share of global energy consumption, and demand for electricity keeps growing, driven by population growth, urbanisation and the spread of air conditioning. One of the main obstacles is intermittency: the sun does not always shine and the wind does not always blow. Without efficient ways of storing energy, power grids must rely on conventional plants to meet demand at night or on calm days.

Battery technology has improved considerably, but large-scale storage remains expensive. Engineers are also exploring alternatives such as pumped hydroelectric storage, in which water is pumped uphill when electricity is abundant and released to drive turbines when it is scarce.

The expansion of renewables also raises social and environmental questions. Large wind and solar projects require vast areas of land, and in some regions local communities have complained that they were not consulted before construction began. In addition, the minerals used in batteries and panels, such as lithium and cobalt, are often extracted under poor working conditions.

Analysts agree that the shift to clean energy is irreversible. The pace of that shift, however, will depend largely on political decisions, grid modernisation and the ability to address the concerns of the people most affected by it.

Renewable energy is no longer a niche industry. Over the last decade, the cost of electricity generated by solar panels and wind turbines has fallen so sharply that, in many countries, building a new solar farm is now cheaper than building a new coal or gas power plant. As a result, investment in clean energy has surpassed investment in fossil fuels for the first time in several major economies.

Despite this progress, the transition is far from complete. Fossil fuels still account for the largest share of global energy consumption, and demand for electricity keeps growing, driven by population growth, urbanisation and the spread of air conditioning. One of the main obstacles is intermittency: the sun does not always shine and the wind does not always blow. Without efficient ways of storing energy, power grids must rely on conventional plants to meet demand at night or on calm days.

Battery technology has improved considerably, but large-scale storage remains expensive. Engineers are also exploring alternatives such as pumped hydroelectric storage, in which water is pumped uphill when electricity is abundant and released to drive turbines when it is scarce.

The expansion of renewables also raises social and environmental questions. Large wind and solar projects require vast areas of land, and in some regions local communities have complained that they were not consulted before construction began. In addition, the minerals used in batteries and panels, such as lithium and cobalt, are often extracted under poor working conditions.

Analysts agree that the shift to clean energy is irreversible. The pace of that shift, however, will depend largely on political decisions, grid modernisation and the ability to address the concerns of the people most affected by it.

Firearms trafficking across land borders has become one of the main concerns of security agencies in South America. Weapons that enter a country illegally often end up in the hands of criminal organisations, fuelling disputes over territory, drug routes and control of local communities. Unlike drugs, which are consumed and must be constantly replaced, a gun can be used for decades and passed from one criminal to another.

Investigators say that smugglers rarely move large quantities at once. Instead, they prefer to split shipments into small loads hidden in cars, buses and lorries, a strategy known as "ant trafficking". Parts are frequently dismantled and transported separately, which makes them harder to detect in routine inspections. In some cases, the weapons are bought legally in neighbouring countries with looser gun laws and then taken across the border.

Monitoring thousands of kilometres of border is a huge task. Many crossings are located in remote areas, with dense forest, rivers or unpaved roads, where there is little permanent police presence. For this reason, authorities increasingly rely on intelligence work and on cooperation with foreign agencies, rather than on physical barriers alone. Tracing the origin of seized weapons, for example, can reveal entire supply networks.

Highway patrols play an important role in this effort, since a large share of illegal arms travels by road. Officers are trained to notice inconsistencies in drivers' stories, hidden compartments and unusual alterations in vehicles. Even so, specialists warn that seizures alone will not solve the problem. Without reducing demand and dismantling the financial structure of criminal groups, they argue, new weapons will continue to flow into the country.

For most of human history, the elderly made up only a small fraction of the population. Today, thanks to better healthcare, nutrition and sanitation, people are living longer than ever before. At the same time, birth rates have fallen in most parts of the world, as families choose to have fewer children. The combination of these two trends is changing the age structure of societies at an unprecedented speed.

In some countries, the number of people over 65 already exceeds the number of children under 15. This shift poses serious challenges for public finances. Pension systems that were designed when there were many workers for each retiree now face growing deficits, since fewer contributors must support a larger number of beneficiaries. Health systems are also under pressure, because older people are more likely to suffer from chronic diseases that require long-term treatment.

Governments have responded by raising the retirement age, encouraging older people to stay in the workforce and, in some cases, attracting young immigrants to fill labour shortages. Such measures are often unpopular, particularly changes to pension rules, which tend to provoke strong protests.

Ageing, nevertheless, should not be seen only as a burden. Older adults frequently care for grandchildren, volunteer in their communities and transfer knowledge to younger colleagues. Moreover, the so-called "silver economy", which includes products and services designed for people over 60, is expanding rapidly and creating new business opportunities.

Experts stress that the countries best prepared for this demographic change will be those that act early, adapting cities, transport and workplaces to the needs of an older population before the pressure becomes unmanageable.

For most of human history, the elderly made up only a small fraction of the population. Today, thanks to better healthcare, nutrition and sanitation, people are living longer than ever before. At the same time, birth rates have fallen in most parts of the world, as families choose to have fewer children. The combination of these two trends is changing the age structure of societies at an unprecedented speed.

In some countries, the number of people over 65 already exceeds the number of children under 15. This shift poses serious challenges for public finances. Pension systems that were designed when there were many workers for each retiree now face growing deficits, since fewer contributors must support a larger number of beneficiaries. Health systems are also under pressure, because older people are more likely to suffer from chronic diseases that require long-term treatment.

Governments have responded by raising the retirement age, encouraging older people to stay in the workforce and, in some cases, attracting young immigrants to fill labour shortages. Such measures are often unpopular, particularly changes to pension rules, which tend to provoke strong protests.

Ageing, nevertheless, should not be seen only as a burden. Older adults frequently care for grandchildren, volunteer in their communities and transfer knowledge to younger colleagues. Moreover, the so-called "silver economy", which includes products and services designed for people over 60, is expanding rapidly and creating new business opportunities.

Experts stress that the countries best prepared for this demographic change will be those that act early, adapting cities, transport and workplaces to the needs of an older population before the pressure becomes unmanageable.