要向外国写信地址用英语怎么翻译呀,比如地址是:河北省保定市北市区和平里街9号楼1单元401室. 先谢谢了

Room 401,Unit 1, Building 9,Hepingli Street,Northern Urban District,Baoding City,Hebei Province

Room 401,Unit 1, Building 9,
Hepingli Street,
Northern Urban District,
Baoding City,
Hebei Province
China

层层递进，从最小的单位开始写，同时要注意结构。