A: Hi. I need a wake-up call tomorrow.

B: What time would you like your wake-up call?

A: I need two calls, one at 7 and another at 7:15.

B: That is no problem at all, of course. You'll get a call at 7:00, and another at 7:15.

A: Then again, I think 7:15 is too early. Change 7:15 to 7:30, please.

B: So, that'll be a call at 7 and another at 7:30. Do you have any other requests?

A: Not just now, but if I do think of something later, I'll give you a ring.

B: Okay, sir. Sleep well.