很多美国社会经济学的数据，80-90 年代是个转折点，连美国和其它发达国家人口的预期寿命也开始分道扬镳。
WENXUECITY.COM does not represent or guarantee the truthfulness, accuracy, or reliability of any of communications posted by other users.
Copyright ©1998-2026 wenxuecity.com All rights reserved. Privacy Statement & Terms of Use & User Privacy Protection Policy
