Dear Sir or Madam/To whom it may concern,

(以下开头两句选一句)

    I am writing this letter to you in hopes that you can help me.As I am planning to(计划要做的事),I have decided to(已经决定做的事).Would you be so kind as to furnish me with some related information?

    I would be grateful if you could be so kind as to provide me with certain essential information regarding the following aspects.

    First of all,(信息1)

    Secondly,(信息2)

    Thirdly/Lastly,(信息3)

(以下结尾三句选一句)

    I shall be very grateful if you could kindly take into consideration my request and grand me a favorable reply at your earliest convenience.

    My appreciation to you for your generous help is beyond word.I would appreciate it if you could contact me as soon as possible.

   Any information you can provide would be greatly appreciated.Please accept my most cordial thanks for your timely assistance,which I will never forget.

                                                                                                   Yours sincerely,

                                                                                                        Li Ming