Food is placed on the tomb of pet dog Xixi at Baifu pet cemetery ahead of the Qingming Festival on the outskirts of Beijing, China March 26, 2016. The Chinese characters on the gravestone read: “Mommy's only good son”. (Photo by Jason Lee/Reuters)

A boy rides on a snow wagon towed by a robot dressed as a Teddy bear, which only moves forward by moving its legs, during the Ice and snow carnival at Taoranting park in Beijing February 9, 2015. (Photo by Kim Kyung-Hoon/Reuters)

A string is used to ensure that the skirts of female members of the honour guard are in the same height from the ground as they prepare for a welcoming ceremony for Congo Republic President Denis Sassou Nguesso outside the Great Hall of the People in Beijing, China, July 5, 2016. (Photo by Jason Lee/Reuters)

Models present creations from the SGM ART MOUSE JI during the China Fashion Week in Beijing, China, 25 October 2020. The fashion​ event runs from 24 October to 01 November. (Photo by Wu Hong/EPA/EFE)

Models wait backstage ahead of their presentation of creations from the YINMU collection by designer Wei Jiang during the China Fashion Week in Beijing, China, 26 October 2020. The fashion event runs from 24 October to 01 November 2020. (Photo by Wu Hong/EPA/EFE)

A cat sits on the empty Great Wall on February 23, 2021 in Beijing, China. Affected by the new coronavirus (COVID-19), the number of visitors to Mutianyu Great Wall in 2020 dropped by about 60%. (Photo by Lintao Zhang/Getty Images)

Models show creations by Chinese graduates from the China Academy of Art School of Design during the Show Town China Graduate Fashion Week in Beijing, China, 13 May 2018. (Photo by How Hwee Young/EPA/EFE)

A woman walks up the steps decorated ahead of the Chinese New Year festival in Beijing, China, Thursday, January 12, 2017. The Chinese Lunar New Year is the most important holiday for Chinese and hundreds of millions are expected to return to their hometown to spend the new year with their family and relatives. (Photo by Ng Han Guan/AP Photo)