1. People grow rice in many countries in the world.

-> Rice is grown in many countries in the world.​ 

2. Graham Bell invented the telephone many years ago.

-> The telephone was invented by Graham Bell many years ago.

3. They have used this car for many years.

-> This car have been used for many years.

4. Lan practices English every day.

-> English is practiced by Lan every day.

5. They will take the garbage out of the city.

-> The garbage will be taken out of the city.

6. Mary sent me this letter two days ago.

-> I was sent this letter by Mary two days ago.

7. People make compost from vegetables.

-> Compost is made from vegetables.

8. You must finish this work before Sunday.

-> This work must be finished before Sunday.

9. She hasn't used this bicycle for a long time.

-> This bicycle hasn't been used by her for a long time.

10. I saw a strange man in my garden yesterday.

-> A strange man was seen in my garden yesterday.

11. They clean the floor every morning.

-> The floor is cleaned every morning.