1. The students have passed all their exams.
Have the students passed all their exams?
The students haven't passed all their exams.
2. They have answered all the questions.
Have they answered all the questions?
They haven't answered all the questions.
3. You have solved the problem.
Have you solved the problem?
You haven't solved the problem.
4. Something has happened to your friend.
Has anything happened to your friend?
Nothing has happened to your friend.
5. She has changed much.
Has she changed much?
She hasn't changed much.
6. Jane has made a lot of mistakes in her dictation.
Has Jane made a lot of mistakes in her dictation?
Jane hasn't made a lot of mistakes in her dictation.
7. We have met him before.
Have we met him before?
We haven't met him before.
