根据括号中的要求改写句子。
1. I heard of the news that the boy was lost.(改为同义句)
I______the news that the boy was lost.
2. You should take care of your little sister.(改为同义句)
You should______your little sister.
3. Our school is not the same as your school.(改为同义句)
Our school is______your school.
4. I think English is not easy to learn.(改为同义句)
I think English is______to learn.
