Properly Worded

A high school senior was inspecting Harvard University, where he hoped to attend the following autumn.

As he was walking across the Quad, he stopped a distinguished-looking man and asked: "Sir, can you please tell me where your library is at?"

The man looked down his nose and replied: "Son, I'm head of the English department, and I can assure you we don't end our sentences with prepositions. Re-cast your sentence in a proper form and I will reply."

"Can you tell me where your library is at, a$$hole?"