A picture of Moon Ji-sung, a high school student who died in the Sewol ferry disaster, hangs in her room in Ansan April 7, 2015. Her dream was to be a flight attendant. Nearly a year after the Sewol ferry sank on April 16, 2014, with the death of 250 students, some families keep their children’s bedrooms intact to remember and honour their loved ones. More than 300 people, most of them students and teachers from Danwon High School, are dead, or missing and presumed dead, after the Sewol ferry sank on a routine trip from the port of Incheon, near Seoul, to the holiday island of Jeju. (Photo by Kim Hong-Ji/Reuters)

Russian cadet preparing before the International Kremlin Cadet Ball in Moscow, Russia 12 December 2017. More than 1500 students from all Russian cadets school attend in Cadet Ball. (Photo by Yuri Kochetkov/EPA/EFE)

A Syrian boy receives treatment at a hospital in the regime-held part of Aleppo on October 13, 2016. Syrian state television said four children were killed by rebel rocket fire on a school in a western regime-held neighbourhood. (Photo by George Ourfalian/AFP Photo)

Nepalese police officers worship a dog during the dog festival as part of Tihar celebrations, also called Diwali, at the Central Police Dog Training School in Kathmandu, Nepal October 29, 2016. Dogs are worshipped to acknowledge their role in providing security during Tihar festival, one of the most important Hindu festivals that is also dedicated to the worship of the goddess of wealth Laxmi. (Photo by Navesh Chitrakar/Reuters)

Children wearing military uniform take part in a parade, held by Russian servicemen, pupils of infant and primary schools, which is a public event to honour World War Two veterans and to mark the upcoming Victory Day, in Rostov-on-Don, Russia on April 25, 2019. (Photo by Sergey Pivovarov/Reuters)

Rosive Silgado Atencio of Columbia lies on the ground after being unable to complete a lift during the women's weightlifting 59kg competition on Day 2 of the Lima 2019 Pan American Games at Mariscal Cáceres Coliseum of Chorrillos Military School on July 28, 2019 in Lima, Peru. (Photo by Ezra Shaw/Getty Images)

Satrio smokes at a kiosk after elementary school on March 3, 2017 in Yogyakarta, Indonesia. Satrio has smoked up to one pack a day and began when he was six years old. (Photo by Ulet Ifansasti/Getty Images)

Kanphitcha Sungsuk, 21, (C), lines up with young men to speak to officers during an army draft held at a school in Klong Toey, the dockside slum area in Bangkok, Thailand, April 6, 2017. Thailand is widely seen as a paradise for gay and transgender people, but many complain of being treated as second-class citizens and the obligation to respond to the draft can be a nightmare when they turn 21. (Photo by Athit Perawongmetha/Reuters)