Question

Here are a few of the things I’ve seen that cause people to destroy their own relationships.

如何分析这句话的结构？
I’ve seen 和cause people to .....如何修饰things？

Answer 1

Here are a few of the things I’ve seen that cause people to destroy their own relationships.
主系表
主语:a few of the things 其中a few of 做定语
系动词:are
表语:here
定语从句1:(that省略)I’ve seen 修饰主语,省略的that代指the things 是从句中的宾语成分.
定语从句2:that cause people to destroy their own relationships修饰主语, that代指the things ,是从句中的主语部分.
这里有几件我曾见过的事情, 这些事使得人们破坏了他们自己的人际关系

Answer 2

here是主语，are的谓语，things是宾语，i've seen和cause people to ....都是things的修饰从句。