Преобразуйте последующие предложения, содержащие глаголы в B Present Indefinite, Past

Преобразуйте последующие предложения, содержащие глаголы в B Present Indefinite, Past Indefinite и Future In-definite, в вопросительные и отрицательные:
1. The last train leaves at midnight.
2. It is important to choose a good job.
3. There are a lot of places of interest in Moscow.
4. Our friends came to see us on Friday.
5. He was an experienced specialist.
6. They will go to the country next summer.
7. It will be difficult to understand them.