Peacocks are seen covered in bags as a protection of their plume during transportation, in Xiangyang, Hubei province, China April 12, 2017. (Photo by Reuters/Stringer)

A Chinese woman wears a mask to protect from particles blown in during a sandstorm as she walks in the street on May 4, 2017 in Beijing, China. Sandstorms are common in northern China during the spring season and are caused when heavy winds from Mongolia in the north brings sand and pollutants that can blanket Chinese cities and cause air quality to deteriorate. (Photo by Kevin Frayer/Getty Images)

Students training to be flight attendants hold books on their heads, chopsticks in their mouths, and papers in between their knees, as they take part in a standing posture practice at a vocational school in Shijiazhuang, Hebei province, China May 4, 2017. (Photo by Reuters/Stringer)

An elderly man uses a fan to shade himself from the sun as he walks in a public park in Beijing, Tuesday, June 7, 2016. Thursday marks the Duanwu Festival, a public holiday in China celebrated with outdoor activities including dragon boat races. (Photo by Mark Schiefelbein/AP Photo)

A man sits on top of a car as he is stranded on a flooded street in Tianjin, China, July 20, 2016. (Photo by Reuters/Stringer)

A man rides his loaded tricycle next to three schoolgirls in Shanghai on December 11, 2015. (Photo by Johannes Eisele/AFP Photo)

An army dog stands up as retiring soldiers salute their guard post before retirement in Suqian, Jiangsu province, China on November 29, 2017. (Photo by Reuters/China Stringer Network)

In this picture taken on December 13, 2017, a woman commutes on a street on a cold day in Baoding. As temperatures dipped below freezing in a northern Chinese village, a group of parka-clad women tried to stay warm as they played mahjong around a small gas stove in a grocery store. (Photo by Fred Dufour/AFP Photo)