改为定语从句
I am the person.I wrote to you
我更改成I am the person whom I wrote to you.
正确答案是 I am the person who wrote to you.
我之前更改那句不对吗?
你更改的那句不对.因为引导定语从句的关系代词who或whom在定语从句中要做句子成分.如；
I am the person who wrote to you中的who代替先行词the person,即：我就是那个给你写信的人.