Нужно написать вопросы к ответам:
1. How long..........?
He was in prison for twenty-eight years.
2. When..........?
He left prison in 1990.
3. When.........?
He became President of South Africa in 1994.
4. How old..........in 1994?
He was seventy-six.
5. When..........?
He got married for the third time on his eightieth birthday.