I am supposed can not dealing with your email in time.求句子分析

I am supposed can not dealing with your email in time.求句子分析
I am supposed can not dealing with your email in time.
存有以下的问题:
1.为什么要用被动(be supposed)
2.Can作为系动词为什么后面的deal with要变成dealing with?
3.原句是否为I am supposed (that) can not dealing with your email in time.
各位好心的大大,有谁能回答一下,第一个问题为什么要用被动呢?