Замените модальный глагол его эквивалентом: When could you put this machine into operation?

  • When were allowed to put this machine into operation?
  • When were you able put this machine into operation?
  • When were you able to put this machine into operation?
  • When were you to put this machine into operation?
Для просмотра статистики ответов нужно залогиниться.