Syrian Internal Security Forces dance in celebration during their graduation ceremony, at Ain Issa desert base, in Raqqa province, northeast Syria, Thursday, July 20, 2017. Some 250 residents of Syria's Raqqa province are the latest batch to graduate from a brief U.S-training course that is preparing an internal security force to hold and secure areas as they are captured from Islamic State militants. (Photo by Hussein Malla/AP Photo)

An Afghan girl carries water on her back as she climbs a hill in Kabul, Afghanistan February 20, 2017. A growing population is straining water supplies in Afghanistan's capital, forcing those who can afford it to dig unregulated wells ever deeper to tap a falling water table. Finding water in arid Afghanistan is virtually always a challenge, but a drop in the groundwater level in Kabul caused by overuse and drought is making it even more difficult for residents, especially the poor. (Photo by Omar Sobhani/Reuters)

Germany, Business couple making love under desk. (Photo by Roman Maerzinger/Getty Images)

This photo taken on February 1, 2018 shows a worker trimming the skin imperfections of a silicone doll at a factory of EXDOLL, a firm based in the northeastern Chinese port city of Dalian. With China facing a massive gender gap and a greying population, a company wants to hook up lonely men and retirees with a new kind of companion: “Smart” sеx dolls that can talk, play music and turn on dishwashers. (Photo by Fred Dufour/AFP Photo)

In this December 13, 2014 photo, Ricardo Alegria holds his donkeys by a leash as he yells to sell their milk in the streets of Santiago, Chile. Alegria, along with his brother Marco, has been selling fresh donkey milk for the past 25 years, and says it's recommended as a vitamin boost. Shot glass size cups of the drink sell for about $2 dollars. Half a liter, which is the most he says his donkeys can give in one day, sells for about $20 dollars. (Photo by Luis Hidalgo/AP Photo)

One of the largest paddle steamers afloat in Britain is the H.M.S. Royal Eagle, former peacetime excursion boat which carried passengers on pleasure jaunts from Tower Bridge to Southend, Ramscate and Margate. Commissioned two years ago as a warship of the Royal Navy, the craft has been in action 52 times against enemy aircraft. The Eagle took part in the evacuation from Dunkirk where she was dive-bombed 48 times and brought home nearly 3,000 British troops. Members of the crew cleaning the paddle boxes of H.M.S. Royal Eagle in London on January 18, 1943. (Photo by AP Photo)

Cambridge policemen, known as “Bulldogs”, lined up for the University Bulldogs Chase, dressed in morning coats and top hats, 7th March 1936. (Photo by H. Allen/Topical Press Agency/Getty Images)

A child performs opera during celebrations on the eight day of Chinese Lunar New Year of the Pig, in Taizhou, Zhejiang province, China on February 12, 2019. (Photo by Reuters/China Stringer Network)