Pollution inside homes and other buildings kills more than 4 million people each year．Many people die as a result of breathing smoke or from cooking over wood﹣powered of coal﹣powered stoves．

    One way to reduce the number of deaths is through cooking equipment powered by the sun．Crosby Menzies，a solar power expert in a South African company，described his latest solar cooker called the“Sol.4”，”It is four square meters of mirrors，six to eight meters in length．It is quite a large cooler．”

    The“Sol.4”works by reflecting （反射）light from the sun off large mirrors．The mirrors direct （把…对准）the light at a cooking pan．Then the light heats the pan with solar energy．Within two minutes，the pan is hot enough to cook sausages and onions．In just four minutes，water can be boiled．That is as fast as cooking with natural gas or electricity．

    The cooker is also much“friendlier”than other models because people do not have to stand in the sun to use it．And people can prepare meals without having to collect firewood or spend money on coal．Suchindividualswould be less likely to have breathing illnesses from harmful smoke．

    At present，the cooker only works when the sun is shining．But engineers are working on a way to make it work without sunlight．

    Each cooker costs about $2000，which is a large amount of money for most Africans．To solve that problem，Crosby Menzies has crated a non﹣governmental organization called solar Cookers for Africa．It plans to raise money through donations to provide poor people with solar cooking equipment．

    Everybody needs water. Everything needs water. We use water to wash the bowls(碗), clothes and ourselves. We use water to plant trees, flowers and crops(庄稼). Where does all water come from? It comes from clouds.

    Some of rain goes into the ground. Many people get it under the ground. Some rain water goes into the hills. It runs into lakes and rivers. Many people get it there.

    In 1826, a Frenchman named Niepce needed pictures for his business .But he was not a good artist .So he invented a very simple camera. He put it in a window of his house and took a picture of his garden .That was the first photo.

    The next important date in the history of photography was in 1837. That year, Daguerre, another Frenchman, took a picture of his reading room .He used a new kind of camera in a different way. In his picture you could see everything very clearly, even the smallest thing. This kind of photo was called a Daguerreotype.

    Soon, other people began to use Daguerre's way. Travelers brought back wonderful photos from all around the world .people took picture of famous buildings, cities and mountains.

    In about 1840, photography was improved .Then photographers could take pictures of people and moving things .That was not simple .The photographers had to carry a lot of films and other machines. But this did not stop them, for example, some in the United States worked so hard. Mathew Brady was a famous American photographer. He took many pictures of great people .The pictures were unusual because they were very lifelike.

    Photographers also became one kind of art by the end of the 19th century. Some photos were not just copies of the real world .They showed feelings like other kinds of art.

A mystery box (盲盒) keeps what's inside a secret. {#blank#}1{#/blank#} But now shops are putting food in them—they are "leftover mystery boxes".

The food inside is near its expiration date (保质期) and will be thrown away if no one buys it. {#blank#}2{#/blank#} They are more and more popular in China's cities, such as Beijing, Nanjing and Chengdu.

In 2021 when I was studying in the UK, I bought leftover mystery boxes from an app called Too Good To Go. Each box cost about 3 to 5 pounds (27 to 45 yuan), and there were usually three to four things inside. {#blank#}3{#/blank#} The box cost 3 pounds but the original price (原价) was around 10 pounds.

{#blank#}4{#/blank#} I felt happy to see kinds of food in it and then I would be happier thinking about how much money I saved. And it helped to cut down wasting of food.

{#blank#}5{#/blank#} Because I can't choose what's in the box, sometimes I got the same kind of food. I had to make other dishes, such as a salad, to make the meal healthier.

Have you ever shouted at your computer because it wasn't working? Of course, your computer can't "shout" back. But Al researchers have been working on computers that can argue and perhaps even win debates (辩论) with humans. 

IBM scientists recently published a paper in Nature about their new AI system— Project Debater. It can debate with people in front of a live audience. After listening to arguments from its opponent (对手), the system can search around 400 million online articles in less than five minutes. And then it looks for ideas that can support its own argument. 

Testing on the system began in 2019. When it debated with Harish Natarajan, a professional debater who holds the world record for the most debate competition victories. The topic was about subsidizing preschool (资助幼儿园) —and Project Debater argued to support this idea. Although Project Debater lost the debate in the end, the audience said it performed very well. Interestingly, 58 percent of the audience said that Project Debater increased their knowledge about the topic—only 20 percent said the same about Natarajan. 

According to Scientific American, results show that the system is able to form logical statements (有逻辑的陈述) . However,  ★ . Their goal is to help humans make better decisions, according to Ranit Aharanoy, manager of the Project Debater team. "It can debate both sides, so it can very quickly help you understand both sides of the problem, so you can have a wider view of the problem and make a more thoughtful decision." Aharanoy said. 

Let's wait and see how the Project Debater will develop in the near future.