A boy doing chin-ups as he takes entrance exams at the Moscow Suvorov Military School in Moscow, Russia on July 11, 2019. (Photo by Sergei Karpukhin/Russian News Agency TASS via Getty Images)

A couple walk in the Retiro park in Madrid on November 17, 2020 as a thick fog falls on the Spanish capital. (Photo by Gabriel Bouys/AFP Photo)

A person watches the sunrise from the Edge observation deck at Hudson Yards on the first day of spring on March 20, 2021 in New York City. (Photo by Noam Galai/Getty Images)

Fog covers the African Renaissance Monument in Dakar, Senegal on February 17, 2021. (Photo by Zohra Bensemra/Reuters)

Members of the LSU Golden Girls dance team sit spaced apart wearing masks, under COVID-19 restrictions, requiring social distancing and masks, before an NCAA college football game between the LSU and the Mississippi State in Baton Rouge, La., Saturday, September 26, 2020. (Photo by Gerald Herbert/AP Photo)

Aeroflot employees with a puppy at the canine service of Aeroflot at Sheremetyevo International Airport in Moscow Region, Russia on October 2, 2020, that has started to train service dogs to detect COVID-19 in people. (Photo by Vladimir Gerdo/TASS)

A painting of a Trabant car bursting through a wall in post unification Berlin, August 1993. (Photo by Steve Eason/Hulton Archive/Getty Images)

Indian brides and grooms wait for the start of a mass wedding in New Delhi on June 15, 2014. Some 92 low-income and disabled couples tied the knot in a free mass wedding ceremony organised by the non-profit organisation Narayan Sewa Sansthan. (Photo by Chandan Khanna/AFP Photo)