A business letter should include the following parts:

1) letterhead: including the name, address and fax or telex number of the sender's company.

2) Date line: year, month and day written.

3) Internal address: the name and address of the receiving company.

4) Address: a polite address to the recipient.

5) The body of the letter

6) Conclusion: The polite language at the end of the letter.

7) Signature: the author's signature.

2, the special part (when writing letters can be increased or decreased according to the specific situation)

1) attachment: indicate samples, sample books, price lists, etc. Attached to the letter.

2) P.S.: After writing the letter, if you think of something important to say, you can add P.S. at the end of the letter to make supplementary remarks.

3) Attention line: I hope the receiving firm will hand over the letter to the handling department as soon as possible.

4) Subject line: Make the basic content or purpose of the letter clear at a glance.

5) Reference number: the number compiled for convenience of filing and classification.

6) CC (abbreviated as C/C): the mark of copying letters to relevant departments.