Singapore, as a small island country, has depended mostly on water supplies from neighboring Malaysia for a long time. Low Pei Chin, a water engineer from the government, told reporters from Agency France-Press, “Singapore is short of natural resources. That is why we are always looking for ways to explore water resources. One major plan is to “collect every drop” and “reuse endlessly”.

The government has created a highly developed system that turns wastewater into drinkable water. Reused wastewater can meet 40 percent of Singapore’s water need. The government expects to meet 55 percent of the need by the year 2060.

Most of the water is used for micro-chip producing factories. But some of it is added to the country’s drinking water supplies. The system also helps reduce ocean pollution, as only a small amount of the treated water is sent into the sea. According to the United Nations, 80 percent of the world’s wastewater runs back into the oceans without being treated or reused.

The Changi Water Reclamation Plant on Singapore’s eastern coast is the main part of the country’s recycling system. The system has a network of tunnels and high-technology treatment centers. Parts of the water treatment centers are underground and wastewater enters the center through a 48-kilometer tunnel. In one building, a network of air flow systems has been put in place to keep the water smelling as fresh as possible. When waste arrives at the plant, it goes through cleaning process before powerful pumps send it to areas above ground for more treatment. There, the treated water receives the last process, through which bacteria and viruses are cleared out. Every day, this large center can treat up to 900,000,000 liters of wastewater.

Now the country also continues to enlarge its recycling system. It will add another underground tunnel and a major water treatment center to serve the western part of the island. The government expects work on the center to be completed by 2025. By the time the project is finished, Singapore will have spent about $7.4 billion on its water treatment systems.

As a natural resource in the earth, geothermal energy can be one of the renewable energy sources. “Geo” means “Earth” and “thermal” means “heat”, so “geothermal energy” means “heat from the earth”.

For centuries, geothermal springs have been used for bathing and cooking. But only in the early 20th century people have started to consider geothermal as a practical source of energy. Today it is used to produce electricity, to heat and cool buildings, as well as for other industrial purposes like fruit and vegetable growth.

The earth takes in solar energy. Geothermal energy becomes available when underground heat is moved by water that is heated when it passes through hot rocks, usually hundreds or thousands of feet deep. Most times, the rocks have lots of holes in them, this heat slowly comes out as forms of hot water and steam.

Inside the earth, the temperature gets about 3 degrees higher as it gets 100 meters deeper. Water passing through hot rocks in the temperatures between 80℃ and 180℃ is able to produce enough heat to warm humans’ living space Iceland, a cold country heats 90%of the houses and buildings of its 320,000 people by using geothermal energy. Geothermal energy resources are widely discovered in China, making the country among the richest in geothermal energy in the world, and its highest geothermal power station in southwest China’s Tibet has been put into operation in 2018. In fact, the usable geothermal resources are found throughout the world and are used nowadays in 83 countries.

Compared with wind and solar energy, geothermal energy cannot be affected by changes in the weather and seasons. We can always get energy from geothermal sources.

But like most other energy sources, geothermal energy also has a defect—it may present environmental problems. The surface of the ground may drop if hot groundwater is taken out without being replaced. In addition, the heated water can contain harmful materials. Apart from that, drilling far enough to make more energy sources costs lots of money.

Although geothermal energy leads to new possibilities, its contribution to the world’s energy future is still too early to tell.

4 . In most cities you go to, you will see walls outside covered with paintings of names and pictures. This is called graffiti. Some people like these paintings, but others do not. People who like them see this graffiti as art, but others believe it makes cities look terrible and that the people who do it should be arrested.

These days in the UK there are still lots of places where you can paint graffiti because most people like graffiti that has a lot of beautiful colors.

▲ ? There are examples of very old graffiti from Greek and Roman cultures. However, modern graffiti started in New York in the early 1970s. It came from parts of the city and the people who wrote it were often teenagers. Graffiti is still part of the city culture in many places in the world today.

Banksy is an England-based graffiti artist. His art is admired around the world. His paintings usually have a political message. Although Banksy has become very famous, nobody knows who he really is. Banksy’s art is so popular that people sometimes try to steal it so that they can sell it at a high price. This makes Banksy angry because the messages in his art are against the idea of money.

In some cities, tourists can take graffiti tours. One of these cities is Bogota in Colombia. There is a lot of beautiful graffiti in Bogota and much of it shows the history of the country or has a political message. You can also see parts of the city tourists do not usually go to. The tour is very popular and is also free. However, they ask you to donate some money if you like the tour. They use this money to help poor Colombian artists.

This is a song millions of Americans hear on New Year’s Eve. This is a song we hear in some classic movies like The Gold Rush (1925), Waterloo Bridge (1931) and It’s a Wonderful Life (1946). This is a song that has different versions around the world. It is called Auld Lang Syne.

Actually, Auld Lang Syne is an old Scottish poem. No one knows who wrote the poem first. However, a version by Scottish poet Robert Burns was published in 1796. The title Auld Lang Syne is believed to be an old Scottish way of saying “a long time ago”. The opening lines of the song “Should auld acquaintance be forgotten, and never brought to mind? Should auld acquaintance be forgotten, and auld long syne?” mean we should have a drink in honor of whatever is passing, and remember old friends. In Scotland, on New Year’s Eve it’s a tradition to play the song with its national instrument called bagpipe to welcome the new year. Bagpipe makes special sound and it has a special look, with a bag at the bottom and one or several pipes*connected to the bag. And the bagpiper, who plays this instrument, is required to wear Scottish traditional clothes kilts.

When the Scots moved to America in the 1800s, they brought the song with them. But the Canadian bandleader Guy Lombardo made it well-known to the public. In 1965, he explained to a reporter of Life Magazine how he connected the song with New Year’s Eve: “Auld Lang Syne is our theme song. We end every dance with it.”

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Cathy Hackl’s son wanted a party for his 9th birthday. He wanted to hold the party on Roblox, a website where users can play and create games. Roblox is part of the metaverse. This is a virtual-reality space. There, users can interact with other people and digital environments. Virtual reality is a three-dimensional simulation of a real-life image or environment. “They hung out and played, ” Hackl said, “Just because it happens in a virtual space doesn’t make it less real.” The term metaverse has become popular. Today, people are spending more of their lives in virtual spaces.

The word metaverse comes from a science fiction book from the 1990s. But the metaverse has been around longer than that. Online communities have existed since the 1980s. We enter the metaverse through a screen. This could be through virtual reality(VR). It could also be through augmented reality(AR). Augmented reality covers computer-generated images on the real world. These experiences create a greater blending of our virtual and real lives. But these two worlds already cannot be separated and we don’t even need any headsets, such as VR glasses. Think about the Didi Taxi app. It uses location data to tell drivers where their cars are.

The metaverse is an expansion of the Internet. There are lots of Internet problems to solve already. Still, many people say it has real benefits. They say it can increase social networks and improve mental health. Hackl is a metaverse expert, and she’s African. She says, “You can encourage a lot more people to join and build social relations.” For those already spending part of their life in the metaverse, that building has begun.

Carrie Tatsu runs a business in the metaverse. But she wants her kids to spend time in the real world. “It’s so important for humans to be with humans in real life, ” she said, “I think as kids grow up in this space, it’s important for them to take part, go smell a flower here, walk on a trail, have a real conversation with a friend. Even though you can simulate that, the simulation is not the same. ”

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7 . ①Anyone watching the Winter Olympics in Beijing, China over the last few days has seen lots and lots of snow—man-made snow. No other cities have held the Winter Olympics on almost 100% artificial snow before.

②This year’s Winter Olympics was held in Beijing, China, and in two areas northwest of Beijing, Yanqing and Zhangjiakou. The areas get cold in winter, but they don’t get a lot of natural snow. That’s because they’re close to the Gobi Desert, and are generally very dry.

③That meant _______. China took water from a reservoir which helps supply Beijing’s drinking water and sent it to a nearby river. To carry the water to the mountains for making snow, the country ran miles and miles of pipes. China says making the snow took about 49, 000 gallons of water. Outside experts say it probably took a lot more water than that.

④China paid an Italian company called Techno Alpin to make the snow. Techno Alpin made artificial snow at several earlier Winter Olympics. For the snow in this year’s Olympics, Techno Alpin laid over 40 miles (64 kilometers) of pipes and brought in hundreds of snow-making machines. Even with all those machines, making the snow for this year’s Games took seven weeks.

⑤In recent years, it has become more and more common to use artificial snow at winter sports events. That’s true even in places that used to have a lot of snow naturally. Some artificial snow was used in the Winter Olympics in 2010 and 2014 because of warm weather. In the 2018 Games in PyeongChang, South Korea, almost 90% of the snow was man-made. As the world warms because of climate change, problems like this are expected to become far more common. Michael Mayr, who leads Techno Alpin in Asia, says, “You could not have winter sports now without man-made snow.”

10 . Up to one quarter of the world’s population use chopsticks as their main eating tools. Called kuaizi in Chinese, chopsticks were developed in China about 5,000 years ago. Often made from wood, chopsticks allow users to pick up pieces of food by clamping together and releasing the sticks with the thumb and first three fingers.

Before the invention of chopsticks, the Chinese used only their hands to eat. One reason why chopsticks were invented is that eating with one’s hands allowed some people to take more food than others. This was considered rude, so using chopsticks, which limited the amount of food that could be taken at one time, was thought to be a more polite practice. Another one was about the great Chinese thinker Confucius. He refused to use knives at the table, feeling that they reminded eaters of the slaughterhouse, so he preferred chopsticks.

At first, chopsticks were used only by nobles. Later on, during the Western Han Dynasty, commoners began to use chopsticks as well. But at that time, people used chopsticks only to eat side dishes, because they liked spoons more than chopsticks. Then, during the Northern Song Dynasty, noodles became a popular dish. It is very difficult to eat noodles with a spoon, so chopsticks were accepted by more people and were used more often. Today, chopsticks are the main eating tools in China, Japan and Vietnam, and people from countries all over the world commonly use these tools while eating Asian food.