Give the proper translations of the Russian and English word combinations

Транспортный тоннель, автодорожный тоннель, судоходный тоннель, горнопромышленный тоннель, гидротехнический тоннель, равнинный тоннель, сооружение тоннеля открытым способом, сооружение тоннеля горным способом, тоннель прямоугольного сечения.

Railway tunnel, pedestrian tunnel, combined tunnel, service line tunnel, mountain tunnel, shield driven tunnel, horseshoe section tunnel.

Answer the questions using the information from the text and your own ideas.

1. What do we call a man-made horizontal underground passageway?

2. What purposes are tunnels excavated for?

3. Why is tunneling so expensive?

4. What does tunnel classification depend on?

5. What cross-section shape is the best one for a metro tunnel?

6. What cross-section shape is the best one for a railway tunnel?

7. Is it possible to construct a sub aqueous tunnel by the cut-and-cover method?

8. What do we call a tunnel laid at a depth of 12 m?