职业流动
参考答案：
是劳动者为追求自身的发展、寻求自己的价值，而改变工作岗位、改换职业的行为。
以下哪个项目不属于常规检验中的项目，（）。
A.工频耐压试验
B.基本误差测定
C.潜动试验
D.冲击电压试验
In western culture,21 was the age________ young people traditionally received a key to their parents’ door, as a symbol of entering adulthood.
A．in which
B．on which
C．at which
D．to which
