School teachers and staff members take part during an active shooter training at James I. O'Neill High School in Highland Falls, New York, U.S., December 12, 2017. (Photo by Eduardo Munoz/Reuters)

A woman laughs as she takes part in the “Domingo Fareleiro” (Floury Sunday in Galician) festival in the village of Xinzo de Limia, northwestern Spain, on January 21, 2018. Domingo Fareleiro (Floury Sunday) takes place annually in Xinzo de Limia, Spain, in a unique celebration that gives the starting signal for a long festive period known as Entroido, or Carnival. (Photo by Miguel Riopa/AFP Photo)

Women take part in an annual block party known as “Banda do Candinho e Mulatas” (Candinho Band and Mulatto Women), during carnival festivities at Bixiga neighbourhood in Sao Paulo, Brazil February 7, 2018. (Photo by Nacho Doce/Reuters)

Competitors stretch before taking part in day three of the World Irish Dancing Championships on March 26, 2018 in Glasgow, Scotland. The World Irish Dancing Championships are taking place in Glasgow this week at the Royal Concert Hall, with more than 14,500 dancers and supporters expected to travel to the championships which has run for more than forty years. (Photo by Jeff J. Mitchell/Getty Images)

Competitors take part in the International Medieval Combat Federation World Championships at Scone Palace on May 10, 2018 in Perth, Scotland. Thousands of visitors are expected to attend the crowning place of Scottish Kings, Scone Palace for the IMCF World Championships which has five hundred competitors and officials from all over the world, from the UK to as far afield as Australia, South Africa and Mexico. (Photo by Jeff J. Mitchell/Getty Images)

Ministry of Defence handout photo of Chinooks from RAF Odiham as they take part in the Royal Air Force flypast over central London to mark the centenary of the RAF on Tuesday, July 10, 2018. (Photo by SAC Pippa Fowles (RAF)/PA Wire)

Undated handout photo of members of Ballet Ireland during a photocall on Edinburgh's Calton Hill before taking part in the Edinburgh Festival 2018 in Edinburgh, Scotland. Issue date: Tuesday, August 7, 2018. (Photo by Julie Howden/Culture Ireland/PA Wire)

A woman collects lotus flowers at a lake in Hanoi, Vietnam, 20 June 2018. Lotus flowers, that bloom every June, are collected by Vietnamese people for their inner parts to be mixed with tea for fragrance. (Photo by Luong Thai Linh/EPA/EFE)