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　　On Sunday, April 22, people all over the world take times out to appreciate(珍惜)the earth that we all share．It's Earth Day, a special day to learn about our planet(星球)and how to take care of it．

　　On Earth Day, some people listen to speeches about the environment．Others help clean up their offices or save water and electricity at home．Your parents many even decide to take a day off from driving their cars．

　　The idea for Earth Day came from a U．S．Senator(參議員), who was worried about

　　Pollution and the health of plants and animals．And the idea quickly caught on(流行起來)．In 1970, the first Earth Day was celebrated．More than 20 million people in cities all over the U．S．took part．Since then, Earth Day has been used to educate people about their role in taking are of our planet．

　　Now, Earth Day has become a global celebration．In l990,200 million people from 140 countries took part in clean-ups, tree planting and other environmental events on Earth Day．

1．When is Earth Day?

2．Who came up with the idea for Earth Day?

3．How many people celebrated the first Earth Day in l 970?

4．Is Earth Day popular around the world now?

5．What is Earth Day?