Make the sentences interrogative and negative: 1. The students have passed all their exams.
2. They have answered all the questions.
3. You have solved the problem.
4. Something has happened to your friend.
5. She has changed much.
6. Jane has made a lot of mistakes in her dictation.
7. We have met him before.
8. The rain has stopped.
9. Our teacher has just returned from London.
10. I have been there very often.

ответ: 1.1. The students haven't passed all their exams.

1.2. Have students passed their exams?

2.1. They haven't answered all the questions.

2.2. Have they answered all the questions?

3.1. You haven't solved the problem.

3.2. Have you solved the problem?

4.1.  Something hasn't happened to your friend.

4.2. Has something happened to your friend?

5.1. She hasn't changed much.

5.2. Has she changed much?

6.1. Jane has not made a lot of mistakes in her dictation.

6.2. Has Jane made a lot of mistakes in her dictation?

7.1.  We haven't met him before.

7.2. Have we met him before?

8.1. The rain hasn't stopped.

8.2. Has rain stopped?

9.1. Our teacher hasn't returned from London.

9.2. Has our teacher just returned from London?

10.1. I haven't been there very often.

10.2 Have I been there (very often)?