Introduction to Nanjing’s Traditional Residential Architectural Art: In Nanjing, the larger multi-entry-style residential buildings are commonly known as “ninety-nine and a half rooms”. The reason is that nine is the largest yang number and also a lucky number. Nine to ten is the end, and the end means going downhill, so China has a saying of "the nine-five master" since ancient times. The residential architecture exhibition in the former residence displays this characteristic style in detail.