怎么做这一题宾语从句复合句?

问题描述:

怎么做这一题宾语从句复合句?
题目是叫我们把两个句子;连成一个含有宾语从句的复合句:
I believe.He can't finish his homework before 9:00.

I[ don't] believe that [he can ]finish his home work before nine.
宾语从句中的否定前移.