“四诗”说也称“二南独立说”，由北宋苏辙首倡，他在自己的著作《诗集传》中提出《诗经》应分为______、_____、____、___四类，即二南当从《诗经•国风》中独立出来，单列一类。这里的“二南”指的是_______、____________。

Why do companies take downsizing

A．Because this is an inevitable tide throughout the world.

B．Because incompetent employees must give their way to new competent ones.

C．Because it is a direct way to reduce cost.

D．Because those employees are too old to work efficiently.