Polite

a) We have received with many thanks your letter of Oct.7, and we take the pleasure of sending you latest catalog. We wish to draw your attention to a special offer, which we have made in it.

Courtesy
b) You will be particularly interested in a special offer on page 5 of the latest catalog enclosed, which you requested in your letter of Oct. 7.

　　怎样通过各种语言形式来表达Courtesy呢？这样的形式很多，现在提供一些常见的供参考：

　　（一） 把命令变成请求的常用形式：

Please, Will you…….., Will you please……..,如：
a) Will you give us more detailed information on your requirement?
b) Will you please (kindly) let us hear from you on these two points?

　　（二） 虚拟式（Past Subjunctive From）如：

a) Would you compare our sample with the goods of other firms?
b) We would ask you to ship the goods by the first available vessel.
c) We wish you would let us have your reply soon.
d) This would seem to confirm our opinion.
e) We should be grateful if you would help us with your suggestion.
f) We think if advisable that you should accept this offer at this price.
g) We should(would) like you to let us know the exact amount.
h) Perhaps you might like to have a look at the actual goods.
i) We might be of some service to you in a similar case.

　　以上的b, f, g, 也可用 will, shall, may, 但是用Past Subjunctive Form则表示更客气和婉转些。

　　（三） 缓和用法（Mitigation）

　　为了缓和过分强调或刺激对方，常用:We are afraid, we would say, we may(or, might) say, we(would) think, it seems(or would seem) to us, we(would) suggest, as you are (or: may be) aware, as we need hardly point out等等表达法来缓和语气，如：

a) It was unwise of you to have done that.
　 We would say that it was unwise of you to have done that.
b) You ought to have done it.
　 It seems to us that you ought to have done it.
c) We cannot comply with your request.
　 We are afraid we cannot comply with your request.
d) Our products are the very best on the market.
　 We might say that our products are the very best on the market.
e) You must keep the matter to yourselves.
　 You must, we would add, keep the matter to yourselves.
f) You must cut off your order in half
　 We would suggest that you cut your order in half.
g) We have not yet had your reply.
　 It appears that we have not yet had your reply.

　　（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。应尽可能避免使用demand而改用request如：

　　We request your immediate payment.

　　b) We are disgusted with your manner of doing business.

　　disguste意味hate而且有strong feeling of dislike or distasted, 既“厌恶”的意思，　因此，还是婉转或含蓄一些为宜，如：

　　We are not completely satisfied with your manner of doing business.

　　c) We must refuse your offer.

　　Must………带有威胁性的意味（minatory tone），不如改为：

　　We regret that we are unable to accept your offer.
　　Or: We regret that we are not in a position to accept your offer.

　　d) We want you to assist us

　　带有傲慢或长者的口吻（superior tone），不如改为：

　　Your assistance would be appreciated.

　　（六）　使用高兴，遗憾，感谢等词汇及表达法

(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。
　
　　写信要做到Courtesy，但要注意
(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.

(c) 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.