We felt it a pity that the research team failed to

题目

We felt it a pity that the research team failed to
such a plant _______ had been described in the botanist's diary.
答案是as,为什么,这是什么从句?
谁能分析一下句子结构？

答案

定语从句,as 引导定语从句,在从句中做主语.