In this picture taken on January 11, 2021, young gymnasts train at the Li Xiaoshuang Gymnastics School in Xiantao, Hubei province. This summer's delayed Tokyo Olympics, which are now due to start on July 23, 2021, will be the defining moment for Chinese gymnasts who have trained relentlessly since as young as age four in the pursuit of gold. (Photo by Nicolas Asfouri/AFP Photo)

A man wearing an illuminated atmospheric diving suit as part of an installation titled “What Lies Beneath” looks at members of the public during the Vivid Sydney festival of light and sound in Sydney, Australia, May 26, 2017. (Photo by Steven Saphore/Reuters)

Rotterdam based SMIT and Livorno based NERI salvage workers start their work of diesel recovery on a pontoon from the the cruise ship Costa Concordia that lies stricken off the shore of the island of Giglio on January 24, 2012 in Giglio Porto, Italy. (Photo by Laura Lezza/Getty Images)

A partially burned American flag lies on the street near the spot where Michael Brown was killed before an event to mark the one year anniversary of his killing in Ferguson, Missouri August 9, 2015. (Photo by Rick Wilking/Reuters)

A woman lies injured after an incident on Westminster Bridge in London on Wednesday, March 22, 2017. A police officer has been stabbed near to the British Parliament and the alleged assailant shot by armed police. Scotland Yard report they have been called to an incident on Westminster Bridge where several people have been injured by a car. (Photo by Toby Melville/Reuters)

Aerobatic aircrafts fly during a performance at the Airshow Zhengzhou 2017 in Zhengzhou, capital of central China's Henan Province on April 27, 2017. The 5-day air show kicked off in Zhengzhou on Thursday, aiming to build a general aviation gathering center for business and communications. (Photo by Li An/Xinhua via ZUMA Wire)

A Philippine Airlines A300 Airbus plane lies near the service road of a highway south of Manila after it overshot the runway, September 19, 1987 in Manila upon landing from Singapore. Nobody was injured among 135 passengers and crewmen on board. (Photo by Bullit Marquez/AP Photo)

Jing Li (L) and her husband Ke Xu wear Tibetan traditional costumes as they pose for their wedding photos in front of Tibetan prayer flags at the Nianqing Tanggula mountain pass in the Tibet Autonomous Region, China November 18, 2015. Jing, 22, and her husband Ke Xu, 23, both from Shiyan in northwestern Hubei province live in Tibet for three year. The couple married last month. (Photo by Damir Sagolj/Reuters)