A train attendant helps a passenger to adjust her seat at the business class carriage on a CRH 380A bullet train Thursday, June 16, 2011. (Photo by Reuters/China Daily)

A citizen rides in smog on December 20, 2016 in Jinan, Shandong Province of China. Air quality index (AQI) readings exceeded 400 and some schools have suspended classes in Jinan. (Photo by VCG/VCG via Getty Images)

The 2016 Greenwich Village Halloween parade, October 31, 2016 in the Manhattan borough of New York City. (Photo by Anthony Causi)

A model has her hair done backstage before the Taoray Wang fashion show during New York Fashion Week in New York, New York, 09 February 2019. New York Fashion Week for designer's autumn and winter lines is being held from 06 to 13 February 2019. (Photo by Peter Foley/EPA/EFE)

A model (C) looks at her mobile phone while backstage before the araisara Sara Arai Collection show during China Fashion Week in Beijing on March 27, 2015. China Fashion Week runs from March 24 to March 31. (Photo by Wang Zhao/AFP Photo)

TV personality Kylie Jenner attends the 2014 MTV Video Music Awards at The Forum on August 24, 2014 in Inglewood, California. (Photo by Steve Granitz/WireImage)

Firework display from the top of the Sky Tower to welcome the New Year on January 1, 2015 in Auckland, New Zealand. (Photo by Dave Rowland/Getty Images)

Bus ushers leap as they pose for a group photo during a meeting one day ahead of the opening session of China's National People's Congress (NPC) at the Great Hall of the People in Beijing, Monday, March 4, 2019. (Photo by Mark Schiefelbein/AP Photo)