Question

How can write formal and informal letter?

Answer 1

Formal Letters:
- Address the concerned person, along with his/her full address
- Write the present date 
- Give a Subject Line that should briefly talk about the purpose of the letter
-  salutation
- Body of the letter
- Sign off with your signature, name.
2) Informal Letters
- Address of the person you are writing the letter to
- Date
- salutation
-Body of the letter
- Sign off with your name and address

Answer 2

FORMAL LETTER
from adress
date
to adress
       salutation(respected)
intro
body
 conclusion
                                                             YOURS faithfully/obediently
                                                                             name
                                                                                 sd

INFORMAL LETTER
                                                                                            to adress
                                                                                               date
salutation dear
letter
                                                    yours lovingly
                                                             name