The key answer of exercise 8

a)

1. Please contact me within one week of the date of this letter to confirm that these steps have been taken.
2. To resolve this matter, I request that you ...
3. I am writing with regard to ...
4. Yours faithfully,
5. Thank you for your prompt attention to this matter.
6. I have taken up this matter ...

b)

Passive → might be taken, have been taken - in both cases the passive is used to sound very formal and even legalistic. The tone is more distant and impersonal than using the active (we might take, you have taken these steps).

Active → has advised, has (also) indicated - in both cases keeping the focus on the lawyer and what she has done. The message is

'I've got a lawyer behind me!'; should you fail, you remove, you issue, contact me, you need - the tone is more immediate, less distant and therefore more threatening and personal, keeping the emphasis on you. The recipient of the letter will understand clearly that these actions are to be taken by them, the recipient.