First, pay attention to the title at the beginning. For men, you can use dear sir. Yes, ma' am, use dear ma' am. Be sure to pay attention to the manners at the beginning. The first sentence of an email can indicate the intention of writing it. For example, if you want to apply for admission to a school, you can start by writing like this. Application (school name).
At the last sentence of the content, I look forward to your reply, which means to write down my name. Yours faithfully (name)
1 friends and colleagues? Write to a friend/colleague
When writing an email to a friend or ordinary colleague, you can start with "hi" directly. If you have a good relationship with ta, you can also start with expressions like "Hello" or "Hello Tom".
2 for acquaintances? Write to ordinary acquaintances
If you know the name of the recipient, you can start with "Dear Mr. Jones" or "Dear Ms. Jones". For female recipients who don't know whether the other party is married or not, it is safer to use "MS" than "Miss" or "Mrs".
③ Official mail? Official mail
If you don't know the name of the recipient, you can write "Dear Sir" or "Dear Madam". If you don't even know the sex of the other person, you can just write "Dear Sir/Madam".
Write to a group of people? There are more than 1 recipients.
If you have more than 1 recipients, you can write "Dear Customer" or "Dear Partner". If your recipient is from the same company or department as you, you can use "Dear", "Dear Colleague" or "Hello everyone".