Chinese artist Kong Ning poses in a costume symbolizing a butterfly, which is decorated with 365 masks on its wings to represent the number of days in a year, during her performance art at the Badaling section of the Great Wall on the outskirts of Beijing January 1, 2015. Kong, whose works include themes related to China's air pollution problem, named her new performance art “Hua Die” (transforming into a butterfly) and performed it on the first day of the new year as she hopes that China has clean air for this year. (Photo by Kim Kyung-Hoon/Reuters)

A child jumps to touch lanterns hung on a tree ahead of the Chinese Lunar New Year celebrations in Beijing on Thursday, January 16, 2020. The world's largest annual migration begins this week in China with millions of Chinese traveling to their hometowns to celebrate the Lunar New Year on Jan. 25 this year which marks the Year of the Rat on the Chinese zodiac. (Photo by Ng Han Guan/AP Photo)

Visitors look out from a balcony in a quiet mall area with closed retail shops and restaurants only offering takeaway on Tuesday, May 10, 2022, in Beijing. China's capital began another round of three days of mass testing for millions of its residents Tuesday in a bid to prevent an outbreak from growing to Shanghai proportions. (Photo by Ng Han Guan/AP Photo)

A girl runs as she plays in a fountain at a shopping mall in Beijing, Friday, June 23, 2023. Authorities issued a rare red alert for high temperatures in parts of China's capital on Friday, the highest level of warning, as highs were expected to once again climb to around 40 degrees Celsius (104 degrees Farenheit). (Photo by Mark Schiefelbein/AP Photo)

Cheng Liping, whose husband Ju was onboard Malaysia Airlines Flight MH370 which disappeared on March 8, 2014, shows a picture of she and her husband together and an old card with a message given by her husband, at a park near her house where she and her husband used to visit during an interview with Reuters in Beijing July 24, 2014. Cheng said her life has been totally changed since the incident. Their two little sons, who don't know about this incident, keep asking her when their dad is coming back. Six months after Malaysia Airlines Flight MH370, with 239 mostly Chinese people on board, disappeared about an hour into a routine journey from Kuala Lumpur to Beijing March 8, loved ones of missing passengers derive what comfort they can from what's left behind after the world's greatest aviation mystery. More than two dozen countries have been involved in the air, sea and underwater search for the Boeing 777 but months of sorties failed to turn up any trace – even after narrowing the search area to the southern Indian Ocean – long after batteries on the black box voice and data recorders had gone flat. (Photo by Kim Kyung-Hoon/Reuters)

A model stands next to a BMW X6 AC Schnitzer car at Auto China 2012 in Beijing in this April 24, 2012 file photo. Amid the razzmatazz, music and crowds at the Shanghai autoshow on Monday, hundreds of attractive young women, and men, mingled among the stands and company booths, introducing the newest sedans and handing out pamphlets. For years, models have been a staple at China's big autoshows – as much of a draw as the latest car models themselves. 2015 is different – the organisers have banned models from the Shanghai show. (Photo by Jason Lee/Reuters)

Yang Juan, an employee at Goopal Group, takes a nap in her seat after lunch, in Beijing, China, April 21, 2016. Office workers sleeping on the job is a common sight in China, where a surplus of cheap labour can lead to downtime at work. But in China's technology sector, where business is growing faster than many start-up firms can hire new staff, workers burn the midnight oil to meet deadlines and compete with their rivals. Some companies provide sleeping areas and beds for workers to rest during late nights. (Photo by Jason Lee/Reuters)