Passengers travel on the London train and underground system during the Christmas party season, December 18, 2015. (Photo by Paul Hackett/Reuters)

A gibbon drinks from a soft drink bottle, given by a tourist, at a zoo in Kunming, Yunnan province, June 18, 2015. (Photo by Wong Campion/Reuters)

Saraa Mutawkil (R), 18, practises boxing at Al Rabie club in Omdurman May 10, 2016. (Photo by Mohamed Nureldin Abdallah/Reuters)

Girls bath inside a drum on a hot summer day at a field in New Delhi, April 18, 2017. (Photo by Adnan Abidi/Reuters)

Students play in their school yard on the first day of the new school term at a primary school in Baghdad, October 18, 2015. (Photo by Ahmed Saad/Reuters)

A Highland Cow at sunset on the edge of the Marlborough Downs, Wiltshire, United Kingdom on October 18, 2020. (Photo by David White/PictureExclusive)

Security forces' members gesture towards a woman in Santiago, Chile on December 18, 2019. (Photo by Andres Martinez Casares/Reuters)

A woman sandboards on the mountain in Wadi el-Rayan Fayoum, Egypt, November 18, 2016. (Photo by Mohamed Abd El Ghany/Reuters)