Echelons of helicopters fly in the formation that spells the Chinese characters of "Ba Yi", which means Aug. 1, or the Army Day, during a military parade at Zhurihe training base in north China's Inner Mongolia Autonomous Region, July 30, 2017. China on Sunday held a grand military parade to mark the 90th founding anniversary of the People's Liberation Army. (Xinhua/Wang Jianhua)
