letter to a official should have respected sir and things like that then why you have written dear sir. may you explain it?

 To give respect to our teachers

see its typical to understand ur question..... as its not clear....

If some one is dear to u then u can use "Dear ________" and if there is someone whom u respect then u can use "Respected ________"....

 Hi

In Formal Letters such as letter to the editor or an officer we use Respected Sir or Madam.

In Informal letters such as letter to family and friends we use Dear.

I hope this is enough for u to understand .plz thumbs up

this is enough to get 5 marks  you should not coomplain about it