Earth Hour started in Sydney on March 31^st, 2007. It calls on families and buildings to turn off the lights from 20:30 to 21:30 on the last Saturday night of March. In 2007 more than 2.2 million homes and businesses turned off their lights.     And it was supported by 50 million people from thirty-five countries. On March 28, 2010 over 2100 cities in another eight countries took part in it. 
In 2012 in China, there were many cities taking part in this activity, especially some large cities, such as Beijing, Shanghai.... In those cities, many people turned off lights in the hour.  In colleges some students held some activities to make all the students leave their dormitories.
It was 20:30, Beijing time. In Beijing some people were taking a walk with their families or friends.  And in Ningbo some young people were holding a party in a park,singing and dancing. The people from the three cities felt very relaxed.Earth Hour has a variety of activities, but the final goal is the same. That is focusing on (聚焦) climate change and protecting the environment for individuals.

A. Many people would feel bored without lights. B. Earth Hour came to China on that day, too. C. And without lights, they could also enjoy themselves. D. In Shanghai some people were having a nice talk with their friends. E. A year later, on March 29, 2008 Earth Hour became a global activity.