通常可以看作插入结构,因为把这样的结构去掉之后句子仍然完整.类似的句型还有：what we used to call,what is called,what they described as,what can be called,what they regarded as,as we call it,as we know it等.通常翻译为“所谓的…”,可以按照英语原文顺序直接翻译.