South Korea's Black Eagles aerobatics team perform a maneuver during a preview of the Singapore Airshow at Changi exhibition center in Singapore February 14, 2016. The Airshow will take place from February 16-21. (Photo by Edgar Su/Reuters)

A participant jumps on vintage skis during a traditional historical ski race in the northern Bohemian town of Smrzovka, Czech Republic, February 20, 2016. (Photo by David W. Cerny/Reuters)

Iraqi security forces ride in vehicles travelling to Mosul to fight against militants of Islamic State at an Iraqi army base in Camp Taji in Baghdad, February 21, 2016. (Photo by Ahmed Saad/Reuters)

Pakistani street performers sit around fire waiting for customers on a chilly evening in Rawalpindi, Pakistan, Wednesday, February 10, 2016. (Photo by B.K. Bangash/AP Photo)

Shaolin monks of the Dengfeng Zhongyue Shaolin Boxing Culture Troupe from Henan Province in China perform in Valletta, Malta, September 17, 2016. (Photo by Darrin Zammit Lupi/Reuters)

A model is groomed backstage of the Fashion East catwalk show during London Fashion Week Spring/Summer 2017 in London, Britain September 17, 2016. (Photo by Neil Hall/Reuters)

Lightning strikes during a storm over the Ionian Sea in Calabria, Italy on June 27, 2016. (Photo by Alfonso Di Vincenzo/Pacific Press/Rex Features)

Fashion fans pose outside the main catwalk venue during London Fashion Week Spring/Summer 2017 in London, Britain September 20, 2016. (Photo by Neil Hall/Reuters)