一道初二英语题句型转换改为同义句

一道初二英语题句型转换改为同义句Harbin is the coldest city in China today.(改为同义句) ( ) ( ) than ( ) ( ) city in China today.注意city是单数,我觉得题目错了应是Harbin （ ) ( ) than ( ) ( ) city in China today.