This allows the recipient to quickly scan the subject before opening your email and it gives them enough information so they know what to expect. You should include whatever polite greeting you like, such as "Dear". Follow this with the recipient's name.  Left-align the salutation. If you are writing to a close friend you can dispense with the salutation completely and just begin with their first name followed by a comma. Include a blank line between the greeting and the body of your email. Like all other letters, the body of your email should include an introduction, body, and conclusion. However, if writing an email to a close friend, this kind of formatting may not be necessary. When closing an email to a friend, this closing does not need to be formal but should signal that your email is ending. If you are writing to a very close friend sometimes it is perfectly fine to simply end you email with your name, leaving out the salutation all together.

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Write a summary of the previous text in Vietnamese:
Bắt đầu với một mô tả ngắn gọn nhưng chính xác trong tiêu đề email. Bắt đầu bằng một lời chào lịch sự trong nội dung email. Nhập nội dung email. Kết thúc email bằng một lời chào tạm biệt.