我国根据人人口居留时间的长短，将流动人口分为：（）、暂住人口和（）三大类。
参考答案：常住流动人口；过往人口
In the past few years, My Heart Will Go On was a popular song among
young people, ____ were often heard singing it at parties
A．they
B． that
C． who
D．which
检验和试验状态标识的目的是什么？
