A group of aircrafts fly above Tian'anmen Square during a ceremony to mark the 60th anniversary of the founding of the People's Republic of China on Oct 1, 2009. In the past decade, the People's Liberation Army has been an important part of China's development. In 2003, when Severe Acute Respiratory Syndrome (SARS) hit the nation, the army built Xiaotangshan Hospital in seven days and nights; after the Sichuan earthquake in May 2008, the army ran to the rescue and saved many lives; during the 2008 Beijing Olympics and Shanghai 2010 World Expo, the army helped maintain security. [Photo/Xinhua]