The ocean can be a great place to swim and play, it may also be useful in another way. Some scientists think that waves could help make electricity.
   “Have you ever been on a surfboard or boat and felt yourself being lifted up by a wave?” asked Jamie Taylor of the Wave Energy Group in Scotland. “There is certainly a lot of energy in waves.”
   Scientists are working on using that energy to make electricity. The United States and a few other countries have started doing research on wave energy, and it is already being used in Scotland.
   Most waves are created when winds blow across the ocean. “The winds start out by making little ripples (波纹) in the water, but if they keep on blowing, those ripples get bigger and bigger and turn into waves,” Taylor said. “Waves are one of nature's ways of picking up energy and then sending it off on a journey.”
   When waves come towards the coast, people can set up dams(大坝) to block the water and send it through a large wheel called a turbine(涡轮). The turbine can then power an electrical generator(发电机).
   We will never run out of wave power. Besides, wave energy does not create the same pollution as oil and coal do.
   Oceans cover three quarters of the earth's surface. That would make wave power seem perfect for creating energy around the world. But there are some disadvantages that need us to pay more attention to.
   Jamie Taylor said that wave power still cost too much money. He said that its influence on animals in the sea is still unknown. Besides, wave power would get in the way of fishing and boat traffic.
   With more research, “Many of these problems might be solved,” Taylor said. “Finding more energy sources(资源) is very important, for traditional sources of energy like oil and gas may run out some day.”
   In the future, when you turn on a light button, an ocean wave could be providing the electricity!

阅读理解。

Hover Camera(无人相机)

    Wang Mengqiu, the inventor of Hover Camera, was born in Hangzhou in 1982. He once studied at Stanford University in the United States. He became famous overnight(一夜成名) because of the invention.

    Forget selfie sticks(自拍杆)! Compared to other cameras, Hover Camera has many advantages.

    *It can fly and stay in mid-air, track your face and even follow you to make sure it gets the perfect picture.

    *It can be controlled by using a smartphone(智能手机).

    *It records movements with a 13MP camera and takes 4K video.

    *It is the best choice for weddings, sports games and holidays.

    Mr. Wang also said: “The main design consideration is easy and safe to take for the users. It's very light and small. It can be folded(折叠) in two, so it can be easily put into a bag. When the power is low, it can land on the ground safely on its own.”

    It's reported that the company has raised $ 25 million to produce it. As it is still being tested(测试), Hover Camera can be bought later this year.

The price has not yet been decided. But a spokesman says the company hopes to sell it for less than $ 600.

    This is a home of the future, a "smart home", where technology can do almost everything. Imagine we are in the year 2050, ①the computer wakes Tom up in themorning as usual. In front of him is a to-do list of the important events for the day, and it is provided by the computer too. According to Tom's request, the computer serves a list of possible dishes. All the dishes are nice.

    As Tom eats breakfast, the computer reminds him to reply to Lucy. Before Tom finishes his next bite, Lucy's computer receives the message. Then Tom goes to the supermarket. The store's system checks his car when he drives to the pickup area and greets him by name. "Good morning, Tom! Your order is in Case4. Thank you for shopping.'' When Tom removes his order from Case 4, all trades are completed automatically(自动地)over the information superhighway. That is, the money is electronically paid into the bank. Soon after arriving at the office, Tom reads another message from Lucy, telling him that she will go to dinner with him.

    The smart home can also do many other things:

    ◆Find things like keys and mobile phones.

    ◆②        (打开或关闭)machines and lights with your voice.

    ◆Clean your home from clothes to buildings automatically.

    ◆Record everything and everyone entering and leaving the house.

    ◆Take care of each member of the family, young or old.

    ③With the development of technology, the smart home will come true in the future. It is sure to play an important part in our life.

Nigeria is a hot and dry country in Africa where electricity is not available to many homes. Most people grow and sell their own fruit and vegetables. Keeping them fresh in the hot place is a real challenge. Without a fridge, most fresh food goes bad in a couple of days. Throwing away the food means losing money for poor families. Eating the bad food causes serious health problems. 

Local teacher Mohammed Bah Abba was worried about this problem and decided to solve it. As a boy born into a family of clay pot（陶罐）makers, Mohammed knew that these traditional clay pots could keep water even when dry. In the 1990s he used this traditional knowledge and his understanding of science to invent a cooling system（冷却系统）. It worked as a"desert fridge". 

Mohammed's cooling system is made up of two pots —a small pot inside a larger pot. In the space between the two clay pots, there is wet sand. People put the fruit and vegetables in the smaller pot, and cover it with a wet cloth（布）. Then they leave the larger pot in a dry place. When water from the sand evaporates（蒸发）, it causes the temperature in the pots to go down. This way the food in the smaller pot is cool. 

With the pot-in-pot cooling system, food stays fresh much longer. Mohammed's "desert fridge" has improved the lives of thousands of people. So in 2001 he won the Rolex Award for Enterprise, which is for the people who try to make the world a better place. 

 After four months of digging, the Ningbo Cultural Heritage Research Institute shared what they found at the Malangxia site (马廊厦遗址) on August 29. The exciting discovery in Yuyao, Zhejiang Province, China, has helped us leam more about how people lived and how society changed over a very long time.

 The site is 2,000 m² big, and 102 things were found like ash pits(坑), houses, tombs(坟墓), and roads. They were made in the middle and lower parts of the Changjiang River area. Imagine digging up layers(层) of history like layers of cake! The Malangxia Site has five different layers, and each one is like a different chapter in a book, telling us about a different time period.

 The first layer is from the Shang-Zhou dynasties, and we found a special tomb. As we move up to the next layer. Here, we found lots of cool things like houses, pits, tombs, and roads. They are like photos that record the life at that time. The third isn't as full as the others. We only found one tomb. But the fourth layer has a lot of findings, with pits, tombs and holes. These things show us how art styles from the north and south of China mixed together.

Local experts say that the Malangxia Site is the biggest and best-kept archaeological (考古的) site in Yuyao so far. It's like a treasure box full of history that helps us understand how society changed over thousands of years. It's amazing to think that just by digging, we can learn so much about people who lived long ago!