What is the correct format for writing letters?

Letters generally consist of title, greeting, body, ending, signature and date. Details are as follows:

1. Appellation is to write the appellation at the top of the first line, followed by a colon. To show respect and goodwill, you can add the words "Dear" or "Dear" before the title.

2. A greeting is a greeting with two spaces at the beginning of the second line. Use polite language to make the other person feel kind and respected.

The text is written in two lines, usually one thing and one paragraph. Attention should be paid to clear description at different levels, concise and clear language, accurate and popular, simple and clear, don't talk too much nonsense, stay close to the central idea and state your own expression.

Finally, the format is "from here" in two spaces on another line, and "salute" at the top of the next line.

5. The signature and date are the author's name written in the last two lines on the right, and the date written is directly below the name. According to the relationship between the writer and the recipient, you can indicate your identity before your name, such as "your friend XXX, student XXX."

Friend: XXX? ×××× Year×× Month× Day