来源：互联网 2012-03-18 00:00
586. How long has it been since you've heard from your uncle?
587. When was the last time he wrote you?
588. I can't recall how long it's been.
589. I'm always disappointed when I don't get any mail.
590. I feel guilty because I haven't written her lately.
591. What time is the mail delivered on Saturday?
592. The postman always comes at 2 o'clock.
593. I wrote to my uncle last night. I couldn't put it off any longer.
594. I enclosed some photographs in my letter.
595. I didn't know whether to send the letter airmail or not.
596. How long does it take for a letter to get to California?
597. Don't forget to put stamps on the letter before you mail it.
598. He went to the post office to mail a letter.
599. I dropped the letter in the mailbox on the corner.
600. How did you sign the letter? Did you write, "Sincerely yours"?