（四） 运用被动语气 有时，运用被动语气，比主动语气客气，如： a) You made a very careless mistake. A very careless mistake was made b) You did not enclose the check with your order. The check was not enclosed with your order. c) For the past two years, you did not give us any order. For the past two years, no order has been given us. Or: For the past two years, no business has been materialized between us.
（五） 避免（或力争避免）使用语气强烈或容易引起不快的词汇 a) we demand immediate payment from you demand的意思是ask for(sth) as if ordering, or as if one has a right to, 即带有命令意味的要求。
(1) We have pleasure of -ing……. We have pleasure in -ing……. It is with pleasure that we do so It gives us(great, much) pleasure to do so We are pleased for us to do so It＇s a pleasure for us to do so. We are glad(or: delighted) that you do so We shall gladly do so We shall feel happy if you will do so We are happy to do so
(2) 表示感谢的表达法有： We are (very, most) appreciative of your doing so We are gratified to learn that you do so We shall be (or: feel) obliged by your doing so We shall be obliged if you will do so You will oblige us by doing so We shall be grateful to you if you will do so We shall appreciate your doing so We shall appreciate it if you will do so We shall thank you to do so It will be appreciated if……. We are thankful that you do so
(3) 表示遗憾的表达法有： It is a matter for regret that we cannot do so It is with regret that we must do so We express our regret at -ing….. To our regret we cannot do so It is regrettable that we must do so We regret that we cannot do so We regret to do so It is to be regretted that you do so We are regretful that we must do so It is a pity that you cannot do so We are sorry we cannot do so We are sorry to do so 注：以上的表达法只是常用的一部分。
（１） 不要使用已经过时的毫无意义的老套子，如： our esteemed clients; your esteemed letter; your respectable house; your good self(or good selves); your valued order; your esteemed reply等等
（２） 要分清"礼貌"与"卑恭"的界限，如： (a) We are extremely and sincerely sorry for the error and ask that you accept our humble and sincere apology for the undue inconvenience suffered by you. b) We beg to acknowledge receipt of your letter dated 11th December. b) We beg to enclose herewith our invoice. 这三例不是"礼貌"，而是"卑恭"。写商业书信既不要盛气凌人，也没有必要低三下四，更应该注意在商业信中把we beg一类的表达法完全去掉。
以上三例可考虑改为： a) We are concerned about the inconvenience you have suffered, and apologize sincerely. b) We have received your letter od Dec. 11. c) We enclose(herewith) our Invoice. Or: We are pleased to enclose our Invoice.