Thank you / Congratulations / Good Luck
I’m writing to thank you for your hospitality / the wonderful present.
It was so kind of you to invite me to stay with you.
I really appreciated all your help / advice.
Congratulations on passing your exams Roland / your excellent exam results!
I wish you good luck / Good luck in / with your exams / your driving test / your interview.
Don’t worry, I’m sure you’ll do well / pass.
Do be on time, won’t you, and don’t forget to …