Перевести из активной формы в пассивную 1)We have already washed the pipettes.
2)His supervisor offered him the theme of his research
3)They showed her the easiest way to do it.
4)Buffer keeps the pH constant.
5)Boris hadn't done this research before his assistant helped him.
6)In the 1 century they started these engines by hand.Now they start them by electricity.
7)The Primary opened the new research center
1)Thd pipettes were already washed.
2) The theme of research was offered by his supervisor.
3)The easiest way to do it was showed.
4)The pH constant is kept by buffer.
5)This research wasn't done by Boris before his assistant helped him.
6)These engines was started by hand in the 1 century. Now they started by electricity.
7)The new research center was opened by the Primary.
Объяснение: