4. Is it really necessary for us to finish the work today?
Do we need to finish the work today?
5. Learning about other cultures is one of my interests.
I'm interested in  learning about other cultures
6. Unless he phones her immediately, he won't get any information.
If he doesn't phone her immediately, he won't get any information.
7. It's very difficult to leave here after such a long time.
It isn't easy to leave here after such a long time.
8. Let's get together and talk about our presentation before we do it in class.
Why don't we get together and talk about our presentation before we do it in class?