One is building new houses, another one is building new apartment buildings that's commercial instead of-- but it's still adding to the housing stock and the third one is improvements of existing houses.

一种是新建家庭住宅,另一种是新建公寓,用于商业用途而非...,也是存量住房的一部分,第三种是现房改造

耶鲁公开课 - 金融市场课程节选