central to virtually在本句中是什么意思?详见内

题目

central to virtually在本句中是什么意思?详见内
But central to virtually all of these theories has been the role of the "agent of change," the force that initiates and implements material progress.

答案

你没问好,把这个句子的结构都给弄错了～
应该是central to theories 和 virtually all of
意思是“基本上所有这些理论的中心角色都是.”