Cambodia (柬埔寨) is going to open the Angkor Wat temples (吴哥窟) at night to interest more tourists to the poor country.

    Tourism is an important foreign currency earner (外汇收入) for Cambodia. More than 1,000,000foreign people are going to visit it this year, and most of them are from South Korea, Japan and the United States. More than half of visitors will visit the Angkor Wat temples.

    Now visitors must walk out of Angkor Wat temples at sunset, but Cambodia is going to extend (延长) the visiting hours to as late as 8:30p. m.

    "We want visitors to see all views of the temples, even in the dark places where they may not see some of the sculptures and statues," Bun Narith said.

    But as hotels are more and more, people need lots of underground water. People say the uncontrolled pumping (无节制地抽水) of underground water is bad for the Earth under the temples.

    What's a spacewalk? Any time an astronaut gets out of a spacecraft(航天器) while in space, it is called a spacewalk. Astronauts go on spacewalks for many reasons. For example, experiments can be placed on the outside of a spacecraft. This lets scientists learn how being in space affects(影响) different things. By going on spacewalks, astronauts can also fix things instead of bringing them back to the earth to fix.

    When astronauts go on spacewalks, they wear spacesuits to keep themselves safe. Inside spacesuits, astronauts have the oxygen(氧气) they need to breathe and the water they need to drink. To keep the astronauts and the spacecraft safe, the astronauts must leave and go back to the spacecraft through a special door. When on a spacewalk, astronauts use safety tethers to stay close to their spacecraft. Tethers are like ropes, connect the spacewalkers with the spacecraft. They keep astronauts from floating(漂 浮) away into space. Another way astronauts stay safe during spacewalks is by wearing a SAFER. SAFER is worn like a backpack. It helps an astronaut move around in space.

    How do astronauts train for spacewalks? One way is by going for a swim. Floating in space is a lot like floating in water. Astronauts practice spacewalks underwater in a huge special swimming pool. For every one hour they will spend on a spacewalk, astronauts need to train seven hours in the pool. Another way astronauts practice for a spacewalk is by using virtual reality(虚拟现实). It looks and feels just like a spacewalk.

    Today, only three countries have finished spacewalks independently. They are Russia, the United States and China. The first person to go on a spacewalk in the world was Alexei Leonov from Russia. Zhai Zhigang is the first Chinese astronaut to go on a spacewalk. The world record of spacewalks is held by Russian astronaut Anatoly Solovyev. He has been on 16 spacewalks and spent more than 82 hours outside in space.

People love walking through a giant puzzle. In a corn maze(玉米迷宫), they can follow miles of paths and run into lots of dead ends before they finally find their way out. The corn maze has been growing for almost 30 years. 

Simple corn mazes began appearing in the 1980s. In 1993, the first big corn maze created for the public to enjoy was made in Annville Pennsylvania, by Don Frantz and Adrian Fischer. Then, in a corntield as big as two and a half football fields, Mr. Frantz created "The Amazing Maize Maze"with the help of his family and friends. When it was done, almost two miles of pathways snaked through the cornfield. Since then, thousands of corn mazes have been created around the world.

For many farmers, a corn maze means a boost(激增) of extra income. During the opening weekend, about 6, 000 visitors came to get lost in Mr. Frantz's maze. Charging only $5 per person, he earned almost $32, 000in two weeks.

Brett Herbst is also a maze designer. In 1999 he set a world record for the world's largest corn maze, an image of the solar system with nine planets in it. He now has a business called The Maize, which has designed more than 4, 000 mazes around the world. "Corn mazes help people connectwith their roots, "he says. "People are so far removed from farm life that they are drawn to something real, something organic. "

Today, a great number of people enjoy seeking fun in a corn maze. Mr. Herbst says, "When we see families on the farm having fun, we know that they are making memories that will last a lifetime. "

Doorbells are the bells (铃) for people to ring at a door. When someone hears it, he or she can open the door. Do you know that you can ring a doorbell for fish, too? 

Every spring, millions of fish migrate (洄游) along the river in the city to find better places to lay eggs. But in the river, there are many locks (水闸). They stop fish from swimming through. Weerd Lock is in Utrecht, the fourth largest city in the Netherlands (荷兰). When fish get there, they have to wait a long time before the lock opens for boats to pass through. The lock keeper there is glad to open the lock for fish, but he cannot tell when fish want to get through. So in 2021, Mark van Heukelum, a scientist, came up with a good idea to help solve this problem—by using the fish doorbell. 

Under the water near the lock, there's a camera. People from around the world can visit a website (网站) to see fish through the camera. When you see a group of fish waiting, you can ring the doorbell on the screen. And when the lock keeper notices it, he will open the lock for the fish. 

In its first spring season in 2021, people around the world rang the fish doorbell more than 100,000 times. If you want to join them to help fish, visit the website and ring the fish doorbell next spring.