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　　One cool April 22 morning, people started the day as usual．Yet it was not a normal day．What’s so special about April 22?The answer is simple．It is Earth Day．People all over the world celebrate this important day．The idea of having a special day to celebrate Earth began in the 1960s．Life was very different then．Few people talked or even thought about the environment．Most people had no idea how dirty our air and water were．

　　On April 22, 1970, twenty million(百万)Americans joined the first Earth Day activities．They showed that people really did want to do something about the environment．Since then laws have been passed to protect the air, water, land, and animals．

　　The vehicles such as cars and buses you ride in must pass tests to make sure they don’t cause too much pollution．Thanks to this law, cars today release(排放)about half as many bad chemicals as cars did back in 1970．As a result, the air we breathe is cleaner than it once was．

　　Rivers and lakes are also cleaner today than they were in the 1970s．It’s a good thing because they needed a lot of help．The Cuyahoga River in Ohio was so polluted that rubbish and oil on the river even caught fire!Today, the river is cleaner．It no longer burns．It’s healthy enough for birds, fish, and other animals．

　　Now the celebration has spread to other countries．More than 175 countries take

　　part each year．

　　In 2007, people in China paid much attention to a big problem．People were throwing away 27 million plastic bags a day!People had “Bye-Bye Throwaway Culture Week．” They wanted everyone to see how polluted it was to throw away so many plastic bags．In 2008, China passed new laws against them．

　　Every April 22, millions get together to clean and protect Earth．They also celebrate how far we have come．Our job is to put this knowledge to work．You can help keep our planet healthy too!

1．Is Earth Day on April 22?

2．What caught fire on the Cuyahoga River?

3．How many countries take part in the celebration each year now?

4．Why did Chinese people have“Bye-Bye Throwaway Culture Week”?

5．What the purpose of celebrating the Earth Day?