A flag guard formation consisting of officers and soldiers from the army, air force, navy and rocket force of the Chinese People's Liberation Army (PLA) attends a military parade to mark the 90th anniversary of the founding of the PLA at Zhurihe training base in north China's Inner Mongolia Autonomous Region, July 30, 2017. The formation was guarding the flag of the Communist Party of China, the national flag and the flag of the PLA. [Photo/Xinhua]