7. In response to your letter of l0th May, I wish to say that
8. In answer to your favour of the 5th May regarding... I reply as follows:
9. Answering your letter of the 8th of February re..., I would say that
10. In reply to your letter of February 8th, I inform you that (of)
11. Replying to yours of the 8th of February regarding..., I would say that
12. Replying to your favour under date of February 8th re..., I say that
(7)非常遗憾,我们奉告您关于,等。
l. We regret to inform you that (of)
2. We are sorry to have to draw your attention to
3. We regret to have to say that
4. We regret to advise you that
5. We very much regret to announce you that
6. It is most regrettable that we have to inform you that (of)
7. It is with our greatest regret that we must inform you that (of)
8. To our greatest regret we must herewith inform you that (of)
9. It is a matter for regret that I have to inform you that (of)