请问新概念英语的这句话,是什么语法结构?

问题描述:

请问新概念英语的这句话,是什么语法结构?
新概念英语第三册第12课里有一句这样的话“perhaps there is an element of truth in both these picture,but few of us had an opportunity to find out”,这里为什么要用had an opportunity ,而不是have an opportunity.

我去看了下原文,其实是but few of us have had an opportunity to find out.
用的是现在完成时,表示从过去开始到现在一直都很少有人有机会发现这一点.