For one of my Engineering Courses, I had to write a professional Business Letter to inform my hypothetical employer of my analysis about two alternatives, and which one of them is better.
For this letter, as I was communicating directly with the employer, and using my own calculations and results, I thought first person would the right way to write (I used lots of "I", some of "my" etc.). Although I think I did a decent job, the professor took lots of points off saying that my letter should always be in third person.
I hope someone who is familiar with this matter can help me shed some light on this matter. Should business letters always be written in third person? I am not compatible with the professor, so I figured I should check online first, just to be sure. I am not a native speaker, so any information and advice, no matter how trivial, would be greatly appreciated.
Thank you very much.