17. Many thanks for your latter of the 5th June
18. Very many thanks for your letter of May 5
19. In acknowledging receipt of your letter of the 5th June, ...
20. Your favour of the 5th May has just reached me
21. Your favour of the 5th May is duly received
22. Your favour of the 5th May is now before me
23. Your promised letter under date (of) the 5th June has just reached us
(6)特回答贵公司某月某日函所叙述有关事项等
1. I have the pleasure of stating, in answer to your inquiry of the 4th inst, that
2. In reply to your letter of the 5th of May, I have to inform you that (of)
3. I hasten to answer your inquiry of the l5th May, by stating that
4. We are in receipt of yours of the 5th June, in reply to which we are pleased to state that
5. In reply to yours of the l0th May, relative to..., I would say that
6. I am in receipt of your favour of the 7th May, and in response I inform you that (of)