Women wearing flower and sprout-like hairpins walk past an advertisement board in Beijing, China, September 25, 2015. Wearing antenna styled hairpins in the shape of various flowers and plants at scenic spots has become a new trend in Beijing. (Photo by Kim Kyung-Hoon/Reuters)

Ma Jiaqi, 5, and her mother arrive at Beijing Railway Station for their train to Changchun of Jilin province, in Beijing, China, January 25, 2016. According to traffic police, over 2.9 billion trips will be made around China during the 40-day Spring Festival travel rush, which started on January 24. (Photo by Jason Lee/Reuters)

A paramilitary police officer (right) turns around as hostesses line up for roll call ahead of the Beijing International Automotive Exhibition in Beijing, China, on Monday, April 25, 2016. Tesla Motors Inc. and BYD Co. are among manufacturers showing 147 new-energy vehicles at this year's show. (Photo by Qilai Shen/Bloomberg)

Vehicles clog a highway during a hazy day in Beijing, China, Wednesday, February 26, 2014. Beijing remained cloaked in hazardous white pollution hiding much of its skyline Wednesday, despite the announced closures or production cuts at 147 of the city's industrial plants. (Photo by Ng Han Guan/AP Photo)

A model showcases designs on the catwalk during Eternal Color Xie Ping Collection A/W 2012-2013 of China Fashion Week at Beijing Hotel on March 27, 2012 in Beijing, China. (Photo by Feng Li/Getty Images)

Dancers prepare before a performance in the backstage area of the Buick exhibition during the “Auto China 2014” Beijing International Automotive Exhibition in Beijing on April 21, 2014. Leading automakers have gathered in Beijing for the kickoff of China's biggest car show, but lackluster growth and environmental restrictions in the world's largest car market have thrown uncertainty into the mix. (Photo by AFP Photo)

Promotional models use their smartphones during their break at the Global Mobile Internet Conference in Beijing May 6, 2014. Mobile Internet industry executives, developers and investors from more than 30 countries took part in the Global Mobile Internet Conference in Beijing, the organiser said. (Photo by Kim Kyung-Hoon/Reuters)

Attendants wait for visitors to the the exhibition entitled “Forging Ahead in the New Era”, showing the country's achievements during his past two terms, at the Beijing Exhibition Center in Beijing on October 12, 2022, ahead of the 20th Communist Party Congress meeting. (Photo by Noel Celis/AFP Photo)