1. Our boss has suggested a new idea.

-> A new idea…has been suggested……………………………………………………
2. You must wash this sweater in warm water.

-> This sweater…must be wash in warm water………………………….………………
3. We sold the last shirt of this style a few hours ago.

-> The last shirt…of the style was sold a few days ago……………………………………
4. They built the Effel Tower in 1889

-> The EffelTowe…was built in 1889…………………………………………………
5. The police are questioning him at their headquarters.

-> He…is being questioned at the police's headquarters…………
6. He sent me a nice gift on my birthday.

-> A nice gift ……was sent to me on my birthday by him………
7. They grow rice in tropical countries.

-> Rice…is grown in tropical countries……….…………………………
8. My father will buy a new car next month.

-> A new car…will be bought by my father nex year………………

9. Someone cleans this room everyday.

-> This room…is cleaned everyday………………………

10. She hasn’t done her homework yet.

-> Her homework…hasn't been done yet…………………………
11. My sister will tell you what time the train leaves

.-> You…will be told what time the train leaves………………
12. We have asked some friends of hers to join us.

-> Some friends …or her have been asked join us…………
17. The teacher is watching them work.

-> They…are being watching to work……….……………………
18. Noone has seen Peter since the day of the party.

-> Peter …hasn't been since the day of the party…………
21. We have to improve all the schools in the city.

-> All the schools…in the city have to be improved………
22. They are going to build a new bridge in the area.

-> A new bridge…is going to be built in the area………....
23. They have buit two department stores this year.
-> Two department stores…have been built that this year………
24. The students are planting trees in the schoolyard at the moment.

->Trees……are being planted in the garden by the students………