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Every year on April 22nd, people celebrate Earth Day all over the world. It is a time to work towards keeping our earth clean. People plan projects to clean up the land, air and water.

U.S. Senator Nelson first thought of the idea for Earth Day in 1962 when he saw polluted rivers and cities covered with smoke. Senator Nelson needed to get support from Americans to clean up the earth. Finally, on April 22nd, 1970, more than 20 million Americans celebrated the first Earth Day! Now many countries around the world celebrate it, and so can you.

How can you celebrate Earth Day? Here are a few ideas:

Join a clean-up project-Clean up your street or a favourite beach.

Save energy-Turn off the lights when you leave a room, and use public transportation.

Use less water.

Reduce, reuse and recycle-practice the three Rs: First, reduce how much you use. Then reuse or recycle what you can.

You can make a difference on Earth Day and every day!

【小题1】Earth Day ________ all over the world on April 22nd every year.
【小题2】Earth day is a time to work towards ________.
【小题3】________ first thought of the idea for Earth Day in 1962.
【小题4】________ Americans celebrated the first Earth Day in 1970.
【小题5】When you leave a room, you should turn off the lights to ________.