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    Plants are very important. This is because plants can make food from air, water and sunlight. Animals and man cannot make food from air, water and sunlight. Animals can get their food by eating plants and other animals. Man gets his food by eating plants and animals, too. So animals and man need plants in order to live. This is why there are so many plants around us.

    There are two kinds of plants: flowering plants and non-flowering plants. Almost all the trees around us are flowering plants. You can know some trees from their flowers and fruit. Non-flowering plants do not grow flowers. You cannot see many non-flowering plants around you.

    If you look carefully at the plants around you, you will find that there are many kinds of plants. Some plants are large and some are small. Most of them are green. Thanks to the plants around us we can live on earth.

    You may know several kinds of police, traffic police and street police. But have you ever heard of energy-saving (节能) police?

    A group of 22 new policemen went to work in Beijing. They went around the city to see the use of energy in hotels, office buildings, shopping centres and other public places. One of their aims is to make sure that these places have set their air conditioners (空调) no cooler than 26℃.

    They also set up a special phone hotline so that people can tell them which building doesn't follow the rule.

    "If everyone sets the air conditioner at 26℃, Beijing will save 400 million kilowatt-hours of electricity in one summer. That's one third of all the usage of the city in the season, said an advertisement."

    A show was held in Beijing last week on energy-saving technology (技术) and productions to introduce a green life to the public. Environmentally—friendly machines, like a machine that helps collect used bottles, have attracted lots of attention.

    "We want to tell people that there are some ways to protect the environment. Each of us can find effective (有效的) ways to do it in our daily life," said Liu Qianguang, an environmental engineer.

    Have you got an eReader? Are you thinking of getting one? We asked some eReaders owners to give us their opinions.

    There are many things that people like about eReaders. "eReaders are really light, weighing less than most paperbacks," said Nathan Jones, a market researcher. "You can hold the book and turn the pages with one hand. An eReader is definitely more comfortable to read in bed or if you're lying on a sofa, plus mine's got a light so I can read in bed at night without disturbing my partner." Another big advantage is that you can store hundreds of books on them. "eReaders are perfect for travel," said Kiera Smith. "You can have lots of books in one device, instead of carrying loads of books in your luggage." The search functions are also popular. "You can look for a character by their name or for a place just by typing in the word. That's really useful," said Megan Malone, a sales executive.

    One user liked the function for increasing font size. "I've got poor eyesight," explained Harvey Callaghan, an engineer. "But the eReader is perfect for me as I can increase the font size." And Jennifer Saunders said, "I like eReaders because they're ecological. If we buy an ebook, we're helping to save trees as they don't use paper. Also, my eReader is solarpowered, so it only uses renewable energy." Best of all is the availability of hundreds of free books online. "Project Gutenberg has millions of titles and they're all free to download," said another user.

    One of the biggest complaints is that you can't find certain titles. "Many books are simply not available in electronic form," said Daisy Madison, an estate agent. If you want a specific book, one that is older, perhaps, or not a bestseller, it won't be available – at least, that was my experience."

    Others complained about the small delay in turning pages. "The gap between pressing the 'next page' button and the screen showing the page is really annoying," said Joel Bray, a shop assistant. "Also, you can't flick between pages so easily."

So, what do you think?

    Cars make our lives more convenient. But they can also be a problem. For example, fossil fuel(化石燃料) cars mainly cause air pollution.

    To improve the environment, many countries are developing electric vehicles(EVs，电动车). Among them, China is taking a leading role and has created the world's largest EV market.

    Last year, over 40 percent of the 753，000 EVs sold in the world were sold in China, more than twice as large as the number sold in the United States.

    "Filling up a fossil fuel car with gas(汽油) is more expensive than charging(充电) an electric car, " said Wu Hao, who bought an electric car this year.

    However, there are still some problems. It can be hard to find charging piles(充电桩) and the cars can't go far before needing to be recharged.

    Some of these problems are being solved. In 2014, China had 31，000 charging piles. Now China has the world's largest EV charging network, with more than 167，000 charging piles in total.

    Developing EVs is one of many efforts that China has made to cut down pressure on its environment after the government promised to stop increases in carbon dioxide emissions(二氧化碳排放量) by 2030.

    "As China goes, so will the world's car industry，" the Wall Street Journal said. China has taken a leading role in the world's electric vehicle industry.