Question

НЕОБХОДИМО ПОСТАВИТЬ ПРЕДЛОЖЕНИЯ В ПАССИВНЫЙ ЗАЛОГ ПОМОГИТЕ ПОЖАЛУЙСТА 1. Don't disturb him. He's dictating a very important letter to his secretary. 2. She was describing the accident to passers-by when the police arrived. 3. Oh, dear! She's been waiting for me for a quarter of an hour already. 4. What are they looking for? 5. Some stranger offered his help when I fell down in the street. 6. When did he write this book? 7. He speaks in such a low voice that nobody ever listens to him. 8. Mr. Brown is buying a new car. 9. Every woman is pleased when somebody pays her a compliment. 10. They haven't bought anything new lately.

Answer 1

Как то так..
1.  Very important letter is being dictated by him  to his secretary.
2. the accident  was being described by her  to passers-by when the police arrived.
3. I have been being waited by her for a quarter of an hour already.
4. нет пассивной формы
5. I was  offered some stranger's help  when I fell down in the street.
6. When was this book written by him? 
7. He is not listened by anybody, because He speaks in such a low voice
8. a new car is being bought by Mr. Brown  .
9. Every woman is pleased when she is paid by a compliment.
10. Nothing has been bought by Them lately.

Answer 2

Чтобы поставить предложения в пассивный залог, нужно изменить активный глагол на пассивный и изменить соответствующие части речи. Вот предложения в пассивном залоге:

1. He's dictating a very important letter to his secretary, so don't be disturbed.
2. The accident was being described to passers-by when the police arrived by her.
3. Oh, dear! I have been kept waiting by her for a quarter of an hour already.
4. What is being looked for by them?
5. His help was offered by some stranger when I fell down in the street.
6. When was this book written by him?
7. Such a low voice is spoken by him that nobody ever listens to him.
8. A new car is being bought by Mr. Brown.
9. When a compliment is paid to her by somebody, every woman is pleased.
10. Anything new hasn't been bought by them lately.