=>
I/
1. The poem which he read to us has been translated into several languages.
2. I don't agree to help you with your homework.
3. More active roles will be played in the classroom by students.
4. If you don't ride your bike carefully, you may have an accident.
5. Although he was seriously ill, he went to work yesterday.
6. My grandfather, who has been retired for ten years now, used to be an astronaut.