Students training to be flight attendants hold books on their heads, chopsticks in their mouths, and papers in between their knees, as they take part in a standing posture practice at a vocational school in Shijiazhuang, Hebei province, China May 4, 2017. (Photo by Reuters/Stringer)

A model walks the runway during the BLACK TAPE PROJECT show at New York Fashion Week Powered By Art Hearts Fashion at The Angel Orensanz Foundation on September 9, 2018 in New York City. (Photo by Arun Nevader/Getty Images for Art Hearts Fashion)

A cave diver in Anhumas Abyss, Bonito, Brazil. (Photo by Marcio Cabral/Epson International Pano Awards 2018)

Female female male threesome. My bit on the side is my best male friend. (Photo by Laoshi/Getty Images)

An adult specimen of Nannospalax (leucodon) montanosyrmiensis, a variant of the lesser mole-rat (Spalax leucodon) is pictured near Albertirsa, some 60 kilometers southeast of Budapest, Hungary, 12 May 2018. The critically endangered rodent lives in several isolated populations in the Carpathian Basin. (Photo by Sandor Ujvari/EPA/EFE)

This combination photo of images released by HBO shows Emilia Clarke portraying Daenerys Targaryen in “Game of Thrones”. The final season of the popular series premieres on April 14. (Photo by HBO via AP Photo)

Restive woman driving. (Photo by Cultura Creative (RF)/Alamy Stock Photo)

Full length portrait of female skier, Sierra Nevada Mountains in California, USA. (Photo by Anatoliy Gleb/Getty Images)