题目内容
The more specific the subject line is, the better it is.
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Dear sir/madam can be used as a salutation if you don't know the recepient.
Your name and your purpose should be includeded in the beginning of an email.
You should make your message as detailed as you can to make the recepient understand what you said.
You can end your email with some phrases like "yours sincerely".
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