Writing a letter

In a formal letter

• It is not acceptable to use colloquial English, slang and idioms.
• It is not acceptable to use contractions.
• you should write the date in full
• you should put your full name after your signature at the bottom of the letter
• you should break your letter into paragraphs

If you don't know the recipient's name,

• you should start your letter as Dear Sir/Madam

If you began a letter with the recipient's name, you end the letter with yours sincerely (best wishes is used with more informal letter)
If you didn't begin a letter with the recipient's name, you end the letter with yours faithfully
Replay,

• As you requested, I enclose my curriculum vitae
• refer to your order of 12 January/I refer to your calls of 12 March
  

Make a compliant,

• I would like to complain about the service I received at your restaurant recently.

say thank you in advance,

• Thank you for your attention in this matter
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