У меня имеется небольшой вопрос. Предложение из действительного залога в страдательный
1 They were selling flowers in that shop at 10 am yesterday
2 The teacher has explained a new rule
3 The students have returned all the library books before they went on holidays
4 She will have written the letter by 5 o' clock tomorrow

  1. Flowers were being sold in that shop at 10 am yesterday.

  2. A new rule has been explained by the teacher.

  3. All the library books had been returned by the students before they went on holidays.

  4. The letter will have been written by 5 o'clock tomorrow by her.