The key answer of exercise 6

a)

1. being arrested
2. regular raids taking place
3. the situation

b)

1. I could hardly believe it when the police officer told me what had happened.
2. It has been reported that a number of people in the area were affected.
3. It's no use! I've looked everywhere for my wallet but I can't find it anywhere.
4. We would appreciate it if you didn't tell anyone about this.
5. It's surprising how quickly I was able to master the skill.
6. It's no wonder you couldn't find your bag. You left it in the café.
7. A: How much further is it? B: It's not far now.
8. It's a pity that you won't be able to make it to the lunch.
9. It was a warm day for the time of year.
10. It appears that someone has made a mistake.