Letter

Dear Sir,

I am writing you to express gratitude for your services in all this these years, in which you have been working with us.

I know that all your pupils are very thankful for your teaching. I have always had good references about you and your job. More than ninety per cent of your pupils have been passed the final exam. In addition, you have been a good partner with the rest of the teachers of at school, so we will miss you.

I wish hope you now now spend much more time in on your favourite hobby besides teaching: to traveling. (I am guessing that teaching is his job, not his hobby)

I hope we will meet up next weekend for have a lunch and if you want, we could go to play golf after.

Yours faithfully, (Faithfully is for romantic partner or maybe a boss. Is that what you mean? How about "Yours truly" or "Sincerely")

PS: The exercise is a letter for a partner at my work who was retired and I don't know if in this case, the type of letter could be formal o informal. Thanks! If it's a close friend at work, you can probably go informal. If you aren't close with him, formal may work.

Great job!