A：Would you please mail these letters, Lucy?
A：These two are urgent letters and should be sent by registered express airmail. Others are ordinary letters.
B：All right, who should I send them to?
A：It’s sent to Mr. Charles. I believe he is in London.
B：Ok, home or office address?
A：Office address, please. He might be at work when they arrive.
B：Should I enclose this commercial paper with these two letters?
A：Yes, it’s right.
【Note】commercial paper 商业本票，商业票据