This duck walks into a convenience store and
asks the clerk, "Do you have any grapes?" The
clerk says no, and the duck leaves. The next day,
the duck returns and asks, "Do you have any
grapes?" The clerk again says no, and the duck
leaves. The day after that, the duck walks in the
store again and asks "Do you have any grapes?"
The clerk screams at the duck, "You've come in
here the past two days and asked if we had any
grapes. I told you no every time that we don't
have any grapes! I swear if you come back in
here again, and ask for grapes, I'll nail your
webbed feet to the floor!!" The duck left, and
returned the next day. This time he asked, "Do
you have any nails?" The clerk replied, "No," and
the duck said, "Good! Got any grapes?"