请高手分析下这个句子！！

来源：百度知道 编辑：UC知道 时间：2024/05/22 06:30:44
There have been several incidents in which people had financial information either lost or stole.
there have been 是不是there be 句型的完成式？？
为什么要用in which??

是；
which指代前文的incidents,
整句话相当于：there have been several incidents and in these incidents,peaple had financial information either lost or stolen.

是there be的完成时````
in which是关系代词,等于where关系副词