Did you turn off your lights from 8:30 pm to 9:30 pm on March 28? Perhaps you invited your parents and neighbors to join the worldwide event--Earth Hour?     Liao Mingyu,17,from Shenzhen Experimental School,is glad that she and a group of other students from eight high schools in the city jointly made the event even bigger by inviting more citizens to take part.      It all started with an idea to design ways of saving energy after Tree-Planting Day.The students,who are all members of the Environmental Protection Union in their own schools,decided to help raise people's awareness of global warming as the Earth Hour campaign approached.     They worked out a detailed plan to make their idea come true.They wrote to local newspapers,residents,companies and even sent an open letter of proposal to the mayor in order to get support from the government.    "From 8:30 pm to 9:30 pm on March 28,please turn off your lights to save energy and protect our Mother Earth,"the letters said.     To their great encouragement,a local newspaper published their plan and asked people to get involved .The mayor even replied to them via the city's environmental bureau to show his support."It was a surprise recognition,"said the receiver Lu WaIllin,17,from Shenzhen No 2 High Schoo1."The government's support may help our idea be heard by the public."     During the Earth Hour,the green activists saw the rewards of their work when they held a night party in a big local communtiy,Meilinyicun in Futian District.A round 1,000 residents turned off their lights and joined the party.At the party,the green activists shared advice about living eco-friendly lives.     These students have now come up with an even more ambitious plan.    "We've learned from the Internet that so far only four Chinese cities--Beijing,Shanghai,Hong Kong and Baoding in Hebei--have officially joined in Earth Hour,"Liao said."We hope that Shenzhen will become the fifth Chinese city to participate next year." Which of the following statements about Earth Hour is Not true?
Earth Hour is held to raise people's awareness of climate change. Earth Hour is not only held in China but also in many other countries. Earth Hour may admit Shenzhen as a new member in the future. Earth Hour is held on March 28 every year.