Question

The doctor (sent, was sent) for immediately. We (sent, was sent) for the doctor immediately. The porter will (bring, be brought) your luggage to your room. Your luggage will (bring, be brought) up in the lift. He (left, was left) his hat and coat in the cloak-room downstairs. They (lost, were lost) the keys. She will (meet, be met) them in the hall upstairs. At the station they will (meet, be met) by a man from the travel bureau. Flowers (sell, are sold) in the shops and in the streets. They (bought, were bought) a car. English (speak, is spoken) by many people all over the world. They (speak, are spoken) English very well. Hockey (play, is played) in winter. He (lived, was lived) in England two years ago. We (study, are studied) foreign languages at school. Foreign languages (study, are studied) in our school.

Answer 1

The doctor was sent for immediately.We sent for the doctor immediately.
The porter will (bring your luggage to your room.
Your luggage will ( be brought) up in the lift.
He (left,) his hat and coat in the cloak-room downstairs.
They (lost,  the keys.
She will (meet,  them in the hall upstairs. 
At the station they will ( be met) by a man from the travel bureau.
Flowers (, are sold) in the shops and in the streets.
They (bought,) a car.
English (, is spoken) by many people all over the world.
They (speak, ) English very well.
Hockey (, is played) in winter.
He (lived, ) in England two years ago.
We (study,  foreign languages at school.
Foreign languages (are studied) in our school.

Answer 2

1. The doctor was sent for immediately. 2. We sent for the doctor immediately. 3. The porter will bring your luggage to your room. 4. Your luggage will be brought up in the lift. 5. He left his hat and coat in the cloakroom downstairs. 6. They lost the keys. 7. She will meet them in the hall upstairs. 8. At the station, they will be met by a man from the travel bureau. 9. Flowers are sold in the shops and in the streets. 10. They bought a car. 11. English is spoken by many people all over the world. 12. They speak English very well. 13. Hockey is played in winter. 14. He lived in England two years ago. 15. We study foreign languages at school. 16. Foreign languages are studied in our school.

Explanation: - In the given sentences, there are instances of active and passive voice. - In active voice, the subject performs the action, while in passive voice, the subject receives the action. - When transforming a sentence from active to passive, the object of the active sentence becomes the subject of the passive sentence, and the active verb is replaced by a form of the verb "to be" plus the past participle of the main verb. - Here's a breakdown of each sentence:

1. The doctor was sent for immediately. (Passive) - Active: Someone (unspecified) sent for the doctor immediately.

2. We sent for the doctor immediately. (Active) - Passive: The doctor was sent for immediately by us.

3. The porter will bring your luggage to your room. (Active) - Passive: Your luggage will be brought up in the lift by the porter.

4. Your luggage will be brought up in the lift. (Passive) - Active: The porter will bring your luggage up in the lift.

5. He left his hat and coat in the cloakroom downstairs. (Active) - Passive: His hat and coat were left in the cloakroom downstairs by him.

6. They lost the keys. (Active) - Passive: The keys were lost by them.

7. She will meet them in the hall upstairs. (Active) - Passive: They will be met by her in the hall upstairs.

8. At the station, they will be met by a man from the travel bureau. (Passive) - Active: A man from the travel bureau will meet them at the station.

9. Flowers are sold in the shops and in the streets. (Passive) - Active: People (unspecified) sell flowers in the shops and in the streets.

10. They bought a car. (Active) - Passive: A car was bought by them.

11. English is spoken by many people all over the world. (Passive) - Active: Many people (unspecified) speak English all over the world.

12. They speak English very well. (Active) - Passive: English is spoken very well by them.

13. Hockey is played in winter. (Passive) - Active: People (unspecified) play hockey in winter.

14. He lived in England two years ago. (Active) - Passive: England was lived in by him two years ago.

15. We study foreign languages at school. (Active) - Passive: Foreign languages are studied at school by us.

16. Foreign languages are studied in our school. (Passive) - Active: We study foreign languages in our school.