Train attendants take part in a parade training as they visit the national flag guard during a patriotic education event ahead of the 90th anniversary of the founding of the Chinese People's Liberation Army (PLA) in Beijing, China July 25, 2017. (Photo by Reuters/China Stringer Network)

Cave Diver, Anhumas Abyss, Bonito, Brazil: The Anhumas Abyss is an underground cavern with a crystal-clear lake below, more than 260 feet (79 m) deep. A visitor must enter through a narrow opening at the top of the chamber and rappel into the cave. Snorkeling and scuba diving in the lake reveal amazing scenery. Distinctive, conical limestone stalagmites and stalactites occupy the lake and the surrounding area, some reaching 65 feet (20 m) high. (Photo by Marcio Cabral/Nature’s Best Photography Awards 2017)

A stag deer stands in the road in Richmond Park, in west London, Britain, December 27, 2017. (Photo by Hannah McKay/Reuters)

Kerry Katona (L) seen attending OK! Magazine's 25th anniversary party at The View from the Shard on March 21, 2018 in London, England. (Photo by Splash News and Pictures)

A pedestrian carries an umbrella as they stroll past an advertisment as a rainstorm moves through Sacramento, Calif., Wednesday, February 13, 2019. Rain is falling widely in Northern California and is expected to spread south. (Photo by Rich Pedroncelli/AP Photo)

A skier in a festive costume attempts to cross a pool of water at the foot of a ski slope while competing in the annual Gornoluzhnik amateur event to mark the end of the ski season at the Bobrovy Log ski resort in the suburbs of the Siberian city of Krasnoyarsk, Russia, April 14, 2019. (Photo by Ilya Naymushin/Reuters)

Ivorian police officers of the Anti-Riot Brigade (BAE) contain the crowd during a performance by French rapper Okou Armand Gnakouri known as Kaaris during the Festival of Urban Music of Anoumabo (Femua) in Abidjan on April 28, 2019. The performance of French-Ivorian rapper Kaaris at the Festival of Urban Music of Anoumabo (Femua) in Abidjan escalated into violence after a crowd surge, causing some minor injuries, according to an AFP journalist at the concert. (Photo by Sia Kambou/AFP Photo)

A first white-handed gibbon infant born at the Skopje Zoo is seen with his mother in Skopje, North Macedonia on May 9, 2019. (Photo by Ognen Teofilovski/Reuters)