Children enjoy a sledge ride past ice swimming fans at the Zalew Zegrzynski lake in Nieporet, Poland, Sunday, February 25, 2018. A cold wave hit Poland with the temperature minus 8 degree Celsius (17.6 Fahrenheit) during the day and dropping to minus 16 degree Celsius (3.2 Fahrenheit) in the night in central Poland. (Photo by Alik Keplicz/AP Photo)

Iraqi women cry over their brother's body, who was killed by a mortar shell fired by Islamic State (IS) group jihadists on civilians who were gathered to receive aid, in Al-Risala neighbourhood on March 22, 2017, as an ongoing offensive by Iraqi forces to retake the city from the group continues. Iraqi forces launched a major operation to recapture west Mosul – the most-populated urban area still held by IS – on February 19, and have retaken a series of neighbourhoods from the jihadists. (Photo by Ahmad Al-Rubaye/AFP Photo)

A student shouts slogans against Venezuelan President Nicola Maduro during a protest on the main highway in Caracas on March 30, 2017. Venezuela' s Supreme Court took over legislative powers Wednesday from the opposition- majority National Assembly, whose speaker accused leftist President Nicolas Maduro of staging a “coup”. (Photo by Juan Barreto/AFP Photo)

US President Donald Trump' s daughter and senior White House adviser Ivanka Trump (2nd R) poses for a photo on a balcony of the VIP tent at the Olympic sliding centre with US army luge athletes Taylor Morris (L) and Matt Mortensen (2nd L), and US women’s bobsleigh silver medallist Lauren Gibbs (R) before the ski jump tower at the men' s four- man bobsleigh event of the Pyeongchang Winter Olympic games in Pyeongchang on February 25, 2018. (Photo by Eric Gaillard/Reuters)

Bar Convent employee Lauren Masterman relaxes after cleaning a historic George and Arthur Maw tiled floor created in 1867, one of only two surviving examples of this assemblage of tiles, at England's oldest living convent Bar Convent on October 13, 2020. Visitors to the convent are being invited to follow in the footsteps of residents from the last 150 years and enjoy the historic space decorated with rare 19th century floor tiles. (Photo by Danny Lawson/PA Images via Getty Images)

A photograph released to Reuters on August 22, 2014 shows the remains of an ancient Mayan city in Lagunita May 30, 2014. Archaeologists have found two ancient Mayan cities hidden in the jungle of southeastern Mexico, and lead researcher Ivan Sprajc, an associate professor at the Research Center of the Slovenian Academy of Sciences and Arts, says he believes there are “dozens” more to be found in the region. (Photo by Reuters/Research Center of the Slovenian Academy of Sciences and Arts)

Attendants arrive at an inauguration ceremony of a Hello Kitty amusement park in Anji, Zhejiang province November 28, 2014. With an investment of $325 million, Hello Kitty Park will be China's first large scale amusement park scheduled to open to the public on New Year's day. According to state media, there are nearly 60 theme parks being built across China at the moment. (Photo by Carlos Barria/Reuters)

A Sorb egg painter decorates an Easter egg while using bent spoons full of melted wax as coloring at the annual Easter egg market on March 16, 2013 in Schleife, Germany. Easter is a particularly important time of year for Sorbs, a Slavic minority in eastern Germany, and the period includes the tradition of painting Easter eggs that include visual elements intended to ward off evil. Many Sorbs still speak Sorbian, a language closely related to Polish and Czech. (Photo by Adam Berry)