With reference to your letter of... addressed to our head office in Beijing which has been forwarded to us for attention and reply, we have pleasure in stating that...
你方……月……日写给我北京总公司的信已交我方处理答复,我们乐意表示……
We received your letter of... It is gratifying to note that...
你方……月……日来函收到。欣悉……
We received your letter of... We are under the impression that...
你方……月……日来函收到,我们的印象是……
We received your letter of... and are indebted to you for introducing us to…
你方……月……日来信收悉,感谢你方将我公司介绍给……公司。
We owe your address to…
我方从……获得你方地址。
We should be glad if you would let us know whether...
如果贵方告知是否……我们将很高兴。
May we have details of...?
我们可以得到……的详情吗?
We are sending you under separate cover...
兹另封寄上……
We attach for your information the copy of a letter received today from...