Spoken English coversation - Asking permission and giving permission

At the Library

Praveen : Good afternoon, Madam, (greeting)
Librarian : Good afternoon, Praveen. What can I do for you?
(offering to help)

Praveen : I need to get some information on animal cells.
Librarian : What is it for, Praveen?

Praveen : I have to make a presentation of animal cells in the
seminar next week.
Librarian : That’s fine. (appreciating a proposal)

Praveen : Could you tell me where I can get it, Madam?
(making a polite request)
Librarian : Look at that last cupboard. It’s marked

REFERENCE.
Praveen : Do you mean the one next to the LITERATURE
cupboard?
Librarian : Exactly! There are a number of encyclopaedias in that
cupboard. You will find there ‘Children’s Science
Encyclopaedia’. That’s the right book for your
reference.

Praveen : Oh, I see. May I borrow it for a day or two?
(asking for permission)
Librarian : Sorry, the reference books are not for lending.

Praveen : There is no place around. May I sit here and take notes?
Librarian : Yes, you may. (granting permission)

Praveen : Thank you, Madam. (thanking)
Librarian :Welcome. (responding to thanks)