511.We are wrestling with a mass of correspondence.
512.I have to clear off arrears of work and correspondence.
513.I hope to work off most of urgent letters by tomorrow.
514.A second-class letter is slower than a first-class.
515.I’m sorry,sir. It is difficult for letters to reach that place.
516.Will you post this letter for me?
517.I’ll have to get this letter off by tonight.
518.Have you sent that letter off yet? There’s something I want to add to it.
519.Would you be kind enough to translate this letter for me?
520.Would you please mail this letter for me at a nearby post office?