The signature block consists of the actual signature, the typewritten name of the signatory (since many signatures are almost illegible) and the official position of the signatory through the latter may be omitted if it is known to the addressee.
The closing paragraph is again usually a single sentence which reestablishes the atmosphere of courtesy whatever has been the nature of the body of the letter. It is frequently used to signal the action which the writer hopes will follow from the letter.
1. Would you please let as have your reply as soon as possible.
2. We look forwards to your reply by return
3. Kindly acknowledge receipt/keep us informed.