Please RSVP by the date we ask you to RSVP.
If you are coming and not staying for lunch, you still have to pay the registration fee.
You cannot call the day before and expect a seat.
No, I cannot take your credit card over the phone.
When sorting excel spreadsheets, you must select all the relevant cells.
Random comment by my student when we noted there are more staff coming than usual:
"It's a recession, maybe people are hungry?"