In this photo provided by the Singapore Ministry of Communications and Information, Prime Minister Lee Hsien Loong addresses the nation with updates on the Covid-19 situation in the city state Monday, May 31, 2021, in Singapore. Lee said controls to lower coronavirus infections were working, while announcing a move to vaccinate students after a spate of transmissions in schools and learning centers. (Ministry of Communications and Information via AP)(KEMKOMINFO SINGAPURA via AP)