RAF volunteers from stations across the UK, who will be acting as the lining party during the Royal Wedding, practice drills in the Parade square at RAF Holton on April 26, 2011 in Aylesbury, England. The members will make up the Queen's Colour Squadron, and will be lining the route between Buckingham Palace and Westminster Abbey during the wedding of Prince William and Catherine Middleton on April 29, 2011. (Photo by Dan Kitwood/Getty Images)

Sydneysiders walk amongst tar figures placed in the CBD to raise awareness about the damage smoking causes to the body at Martin Place on June 30, 2011 in Sydney, Australia. Each of the tar figures represent the profile of smokers, from the casual weekend smoker to the one with a lifelong addiction. (Photo by Lisa Maree Williams/Getty Images)

Workers attach 288 new Waterford Crystal Triangles on the 2012 Times Square New Year's Eve Ball at One Times Square on December 27, 2011 in New York City. (Photo by Jason Kempin/Getty Images)

Models pose backstage ahead of the Review of Australian Fashion Week show as part of Mercedes Benz Fashion Festival Sydney 2011 at Sydney Town Hall on August 24, 2011 in Sydney, Australia. (Photo by Lisa Maree Williams/Getty Images)

A seven-week-old Persian kitten peers into a goldfish bowl, 9th October 1972. (Photo by William Vanderson/Fox Photos/Hulton Archive/Getty Images)

An Zi, is squashed amongst other commuters in a subway train on his way to work in Beijing, China, November 12, 2015. An, a movie producer, moved to Dongsanqi village in Changping this year. His commute to work can take about 2 hours, with transportation costs topping 200 yuan a month, or about a fifth of his monthly rent. (Photo by Jason Lee/Reuters)

Online hostess Xianggong (L) and other hostesses check their pictures as they gather around the photographer while taking part in a football-themed photoshoot at a photography studio in Beijing March 4, 2015. In China's online hostessing world, men find virtual company and the women can find riches. Xianggong is one of more than 10,000 hostesses on the internet site bobo.com, a live broadcasting web platform where anyone can record themselves singing, playing piano, dancing or just chatting. (Photo by Jason Lee/Reuters)