We have a foreign English teacher leaving, and I hope to make a thank-you card in English with about 50 words to express our gratitude.

Dear (teacher's surname):

I can't believe that after so many days, you will leave us soon. What a wonderful time we spent together! We have all gained a lot in the past time. I will always remember what you did for us. Now that you're leaving, I've thought a lot. What I really want to say is not only thank you, but also my best wishes, that is, I hope you are all right.

Your stink.

(Your name)