A soldier of the Chinese People's Liberation Army Garrison in the Hong Kong Special Administrative Region donates blood in Hong Kong, August 9, 2019. [Photo/Xinhua]

Soldiers of the Chinese People's Liberation Army Garrison in the Hong Kong Special Administrative Region donate blood in Hong Kong, August 9, 2019. [Photo/Xinhua]

Soldiers of the Chinese People's Liberation Army Garrison in the Hong Kong Special Administrative Region pose for a group photo after donating blood in Hong Kong, August 9, 2019. [Photo/Xinhua]

A soldier of the Chinese People's Liberation Army Garrison in the Hong Kong Special Administrative Region donates blood in Hong Kong, August 9, 2019. [Photo/Xinhua]