Union Jack
noun [ C usually singular ] uk/ˌjuː.ni.ən ˈdʒæk/ us/ˌjuː.ni.ən ˈdʒæk/ (also Union flag)
英国国旗
the red, white, and blue flag of the UK
The Chinese anthem was played after the Union Jack was lowered in Hong Kong for the last time. 英国国旗在香港最后一次降下后，奏响了中国国歌。