Taken from The Guardian, an actual letter sent by the British Inland Revenue (IRS to our American Friends).
Dear Mr Addison,
I am writing to you to express our thanks for your more than prompt reply to our latest communication, and also to answer some of the points you raise. I will address them, as ever, in order. Firstly, I must take issue with your description of our last as a “begging letter”. It might perhaps more properly be referred to as a “tax demand”. This is how we, at the Inland Revenue have always, for reasons of accuracy; traditionally referred to such documents.