in the past 30 years china 空格 preat advances in the socialis

20.in the past 40years china ______ great advances in social In the pass 30 years china ____great advances in the cociali housing condition changes in the past 30 years in china Great changes( )place in China in the past 20 years. in the past two years In the past three years in the past few years in the past 100 years The number of colleges in China ( )in the past 20 years. in the past 16 years in the last 16 years there ___ ___ great ___ in China in the past few years 单项选择：Great changes ____ in the past ten years in China .