Britain Soccer Football, West Ham United vs Manchester United, Barclays Premier League, Old Trafford on May 10, 2016. Police play football with a young West Ham fan before the match. (Photo by Eddie Keogh/Reuters/Livepic)

A model presents a creation at the Moschino fashion show during Milan Fashion Week Spring/Summer 2017 in Milan, Italy, September 22, 2016. (Photo by Alessandro Garofalo/Reuters)

Students from St Andrews University are covered in foam as they take part in the traditional “Raisin Weekend” in the Lower College Lawn, at St Andrews in Scotland, Britain October 17, 2016. The weekend, which begins on Sunday, involves rituals for new students, culminating in a foam fight on Monday morning. (Photo by Russell Cheyne/Reuters)

A Hong Kong Vegetarian Society activists lies on a giant plate alongside oversized peas, carrots and cutlery during a protest rally in the tourist district of Tsim Sha Tsui, Hong Kong, China, 23 December 2015. The activists urged passers-by to extend the holiday spirit to animals and to give thoughts to the cruelty inflicted on animals in meat productions. (Photo by Jerome Favre/EPA)

Fighters of the pro-government Popular Resistance Committees militia carry a cannon as they transport it in parts to Yemen's southwestern war-torn city of Taiz December 26, 2015. (Photo by Reuters/Stringer)

A contestant walks the runway during 2017 Miss Great Britain competition at the Mayfair A-list venue DSTRKT on May 11, 2017 in London, England. The pageant hopefuls were battling it out to represent Miss Central London. Miss Great Britain is a female beauty pageant. It is the oldest pageant in the UK, established in 1945. Following World War Two, a number of seaside resorts around the country introduced beauty contests as attractions. (Photo by Jules Annan/Barcroft Images)

These beautiful shots may look like works of modern art – but they are actually close-ups of chemical reactions. The works were snapped with the help of a group of scientists from the University of Science and Technology of China (USTC) in Anhui, China. Here: Zinc reacting with lead nitrate in a soft gel to form lead crystals. (Photo by Yan Liang/Caters News)

A participant falls on vintage skis during a traditional historical ski race in the northern Bohemian town of Smrzovka February 21, 2015. (Photo by David W. Cerny/Reuters)