I have always enjoyed working with you. You have such a fresh personality and seem to get along with all of your co-workers. I generally enjoy my association with you and I'm glad you're part of the (company) team.
After reviewing your last expense report, there are...
Dear (recipient's name),
I have always enjoyed working with you. You have such a fresh personality and seem to get along with all of your co-workers. I generally enjoy my association with you and I'm glad you're part of the (company) team.
After reviewing your last expense report, there are a few items that I question. I'm sure it's just an oversight on your part, but this is the (number) time this year we've had a discussion like this. The first time I questioned your expense report, you said it was carelessness on your part and that you would try harder to remedy this situation. It seems there is still a problem. I have highlighted the expenses I find to be in excess. The enclosed copy is for your reference. Notice that the highlighted examples alone are more the $(amount).
Please provide me with a written explanation of the highlighted items by (date). I expect justification for every item that I question. If you do not comply, I will be forced to terminate your employment.
Please give me a call if you have any questions. I trust everything can be solved to be satisfaction.
Sincerely,
(your name)