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Save the world's trees

    "When it comes tothe Earth, there is no time to waste." says the Earth Day Network. And that isright. Protecting our environment is very important, and World Earth Day wascreated in 1970 to ask more people to protect our environment. On April 22, peoplearound the world celebrate Earth Day.

Every year thereis a special topic, and this year it is "Trees for the Earth", so Earth Daythis year will be all about planting trees. They are planning to plant 7.8billion trees within the next five years.

That's a biggoal, and you might wonder why trees are so important. Because they can take incarbon dioxide (CO₂) and protect the air quality(质量). CO₂ isa chemical in our atmosphere, but humans make too much of it. Each person makesabout 2.3 tons a year, which is bad for the environment.

Well guess what!Planting new trees is important because people cut down a huge number of trees.Last year, there were 3 trillion trees in the world, about 139 billion inChina. But according to China Daily, the world's total number has been almostcut in half since human civilization(文明) began. That's because 15billion trees are cut down every year.

So we need toplant more to make up for（弥补）the ones we lost. One treecan take in 21. 8 kilograms of CO₂ per year. Andit's still one ofthe cheapest and best ways to get rid of CO₂.

    But don't forget that we can also help the environment by cutting down on how much energy(能源) or water we useevery day. Every little thing helps.

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