请原谅我的回信延迟......，等。

　　1. Please excuse my late reply to your very friendly letter of March 1.

　　2. I hope you will forgive me for not having written you for so long.

　　3. I hope you will excuse me for not having replied to you until today.

　　4. I humbly apologize you for my delay in answering to your kind letter of May 5.

　　5. I have to (must) apologize you for not answering your letter in time.

　　6. I must ask you to kindly accept our excuses, late as they are.

　　特此奉告等

　　To inform one of; To say; To state; To communicate; To advise one of;

　　To bring to one's notice (knowledge); To lay before one;

　　To point out; To indicate; To mention; To apprise one of;

　　To announce; To remark; To call one's attention to; To remind one of; etc.

　　1. We are pleased to inform you that

　　2. We have pleasure in informing you that

　　3. We have the pleasure to apprise you of

　　4. We have the honour to inform you that (of)

　　5. We take the liberty of announcing to you that

　　6. We have to inform you that (of)

　　7. We have to advise you of (that)

　　8. We wish to inform you that (of)

　　9. We think it advisable to inform you that (of)

　　10. We are pleased to have this opportunity of reminding you that (of)

　　11. We take the advantage of this opportunity to bring before your notice

　　12. Please allow us to call your attention to

　　13. Permit us to remind you that (of)

　　14. May we ask your attention to

　　15. We feel it our duty to inform you that (of)