The key answer of exercise 13

a)

1. the
2. -; the; the
3. -
4. a
5. -
6. -
7. the; the
8. an
9. the
10. the

b)

1. It's Bogotá.
2. They drive on the left.
3. They speak English and French.
4. One thousand.
5. It's in Tokyo, Japan.
6. He's a British actor. He plays James Bond in Skyfall and other films.
7. It's 380,000 km.
8. It takes about five minutes.
9. England, Scotland, Wales and Northern Ireland.
10. In English, it's the Danube.