LONDON, July 6, 2020 (Xinhua) -- British Prime Minister Boris Johnson (L) and founder of Clap for Carers Annemarie Plas clap outside 10 Downing Street to mark the 72nd anniversary of the National Health Service (NHS) in London, Britain, on July 5, 2020. Britain on Sunday saw a nationwide round of clapping to pay tribute to NHS staff on the 72nd anniversary of its founding.