Students of Hou Kong Middle School participate in a flag-raising ceremony marking the Chinese Youth Day in south China's Macao, May 4, 2018. Friday marked the anniversary of the May 4th Movement, a patriotic campaign that started from universities and was launched in 1919 by young Chinese to fight imperialism and feudalism. May 4th later was established as Youth Day in 1949 by the Chinese government. (Xinhua/Cheong Kam Ka)