A letter is a formal written communication usually used to express the feelings, information, and wishes of an individual or group. The following is a common letter format: 1. Letterhead: Including basic information such as the name, address, date, and zip code of the writer. 2. Information of the recipient: including the recipient's name, address, telephone number, and other contact information. 3. Use polite forms of address, such as 'reverent',' dear', and 'reverent'. 4. Body: Including greetings, body, thanks, farewell, etc. 5. Ending: Use respectful, sincere, heartfelt, and other well-wishes. 6. Sign: Use the writer's signature and date to indicate that the letter is confirmed and responsible. 7. Additional documents: If you need to attach other documents or information such as photos, documents, etc., you need to indicate it at the end of the letter and add the corresponding icon. Seal: Seal the letter, usually with a red or blue postmark to indicate that the letter has been mailed. These are the basic forms of letters. Different cultures and societies may have different forms of letters, but generally, they are made up of the above elements.