I'm looking for an expensive vietnamese place to eat, can you help me find one?
It doesn't look like there are any expensive Vietnamese restaurants. Would you like me to look for a different cuisine type or price range? 
Are there any British food joints?
Graffiti is in the west part of town in the expensive price range, would you like to book that?
Yes, please book a table for 6 on Thursday.
What time shall we make that booking for?
Make it for 11:15 and please give me a reference number.
Alright, your table for 6 has been booked for Graffiti for Thursday at 11:15. Is there anything else I can do for you?
Yes, can I please have the reference number as well for the booking?
Of course, the reference number is 1JR8K2OP. May I assist you with anything else?
No that is all, thank you very much.
You are very welcome. Please feel free to contact us in the future. Have a great day.