Prepositions use: At or Behind?

[Tom]

Hello

Could you please tell me about the correct preposition?

1- I came to your office twice but you were not----------
your desk. ( behind-at )

I have seen both prepositions being used with the word desk.

Tom

[Yankee]

Hi Tom

The word "at" is definitely the best for your example. I'd say "behind" is much less often used than "at".

If you used the word "behind", it would usually be in order to emphasize a person's location in relation to his desk from the point of view of someone else (who is probably in front of the desk).

I'd tend to use the word "behind" more often when talking about, for example, something like a "reception desk".

Amy