Translate the following underlined sentences into English.“舞动的北京”是一方中国之印。这方“中国印”镌刻着一个有着十三亿人口和五十六个民族的国家对于奥林匹克运动的誓言。
IT IS ENGRAVED WITH COMMITMENT MADE TO THE OLYMPIC MOVEMENT BY A COUNTRY THAT HAS 56 ETHNIC GROUPS AND A POPULATION OF 1.3 BILLION. 
