Student or Learner
I am bit good in speaking but problem while writting.Mostly when i try to write email i get confused how to start the email and how to end the sentences.for example if send some file to my bosses i will write like this
I am sending you the link of the file. Please open and add you’re this month activity temporary passwords for this file are admin.
here is link
Example Web Page
if you have any problem during adding your activity feel free to ask me
I would always use their name rather than 'sir':
Dear Mr/Mrs/Ms X,
If you use first names when addressing them, then you could use it here as it's not a very formal letter.