A coach wipes away tears and comforts a girl who was feeling tired during gymnastics lessons at the Shanghai Yangpu Youth Amateur Athletic School in Shanghai, China, May 4, 2016. (Photo by Aly Song/Reuters)

Couple getting intimate on couch. (Photo by Vincent Besnault/Getty Images)

Military policemen take part in an operation at Cidade de Deus favela in Rio de Janeiro, Brazil, on February 01, 2018. (Photo by Mauro Pimentel/AFP Photo)

Gas-masked men of the British Machine Gun Corps with a Vickers machine gun during the first battle of the Somme, 1916. (Photo by General Photographic Agency/Getty Images)

Cheerleaders let their hair fly as they perform prior to a German first division Bundesliga soccer match between 1. FC Cologne and Bayern Munich in Cologne, Germany, March 4, 2017. (Photo by Michael Probst/AP Photo)

Cars drive under a rainbow near Bad Langensalza, Germany, Wednesday, November 2, 2016. (Photo by Jens Meyer/AP Photo)

Omsin, a 25 year old femal green sea turtle, rests next to a tray of coins that were removed from her stomach after a surgical operation at the Faculty of Veterinary Science, Chulalongkorn University in Bangkok, Thailand, March 6, 2017. (Photo by Athit Perawongmetha/Reuters)

Britain's Princess Elizabeth clasps her hands in sympathy as Sergeant Jean Bayliss faints at her feet during an inspection of the guard of honour of the Women's Royal Army Corps at Shrewsbury Castle, Shropshire, on July 6, 1949. (Photo by AP Photo)