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The activity named Earth Hour is held at 8:30~9:30 on the last saturday in March every year
每年3月最后一个星期六，当地时间晚上8：30~9：30

2.To sport this activity,we turn off the light for an hour.
为了支持这次活动，熄灯一小时

3.Taking this activity is in order to Improve the realization in environment and make an respons for the changing climate.
目的：提高环保意识，应对气候变化

4.With the high-speed development,the activity started in 2007 in Syeney has more than 90 countrise and 4000 citise and one billion people took part in.
2007年始于悉尼，之后迅速发展。2009你年约90个国家4000个城市10亿多人参加

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